Latin declension

Grammatical cases

A complete Latin noun declension consists of up to seven grammatical cases: nominative, vocative, accusative, genitive, dative, ablative and locative. However, the locative is limited to names of cities, small islands and a few other words.

They are often abbreviated to the first three letters.

The Latin cases have usually been given in the order Nom–Voc–Acc–Gen–Dat–Abl in Britain and many Commonwealth countries since the publication of Benjamin Hall Kennedy's Latin Primer (1866). This order reflects the tendencies of different cases to share similar endings (see below). For a discussion of other sequences taught elsewhere, see Instruction in Latin.

However, some didactic approaches or schools teach it in the order Nom–Gen–Dat–Acc–Voc–Abl or Nom–Gen–Dat–Acc–Abl–Voc, the order also used before the Latin Primer by Benjamin Hall Kennedy. This order is used in The School and University Eton Latin Grammar (1861), with the ablative case always cited last, and a similar one is used in grammars of Ancient Greek (except without the ablative case, which does not occur in Greek), and has been retained by some modern didactic approaches to allow comparison of Latin and Greek.

Meanings and functions of the various cases

The nominative case marks the subject of a statement and denotes the person or object that performs the action of the verb in the sentence. For example, "Mary is going to the store" or "Mary is my sister". It is also used for the predicate: "Mary is my sister". The nominative singular (for adjectives, masculine nominative singular) is used as the reference form of the word.

The vocative case is used to address someone or something in direct speech. In English, this function is expressed by intonation or punctuation: "Mary, are you going to the store?" or "Mary!" This case is identical to the nominative form in most of the declensions, like in Maria "Mary", nauta "sailor!"; except in the masculine singular second declension (-us → -e; -ius → -ī), e. g. Brutus → Brute "Brutus!", Vergilius → Vergilī "Virgil!", and Greek masculine first declension names, e.g. Aenēās →Aenēā "Aeneas!"

The accusative case marks the direct object of a verb. It also has various other functions, e.g. it is governed by some prepositions. It can be used to express motion towards something, with or without a preposition.

The genitive case expresses possession, measurement, or source. Many of its uses correspond in English to uses of the preposition "of", and in some situations to the English "possessive case".

The dative case marks the recipient of an action, the indirect object of a verb. In English, the prepositions to and for frequently correspond to this case, though there are also many uses of these prepositions which do not correspond to the dative case.

The ablative case expresses separation, indirection, or the means by which an action is performed. In English, the prepositions by, with, from, in and on are most commonly used to indicate these meanings.

The locative case expresses the place where an action is performed. In early Latin the locative case had extensive use, but in Classical Latin the locative case was very rarely used, applying only to the names of cities and small islands and to a few other isolated words. For this purpose, the Romans considered all Mediterranean islands to be "small" except for Sicily, Sardinia, Corsica, Crete, and Cyprus. Much of the case's function had been absorbed into the ablative. In the singular first and second declension, the locative is identical to the genitive singular form, and in the singular third declension, the locative is identical to the dative singular form. For plural nouns of all declensions, the locative is also identical to the ablative form. The few fourth and fifth declension place names would also use the ablative form for the locative case. However, a few nouns use the locative instead of a preposition: bellum → bellī "at war", domus → domī "at home", rūs → rūrī "in the country", humus → humī "on the ground", mīlitia → mīlitiae "in military service", "in the field", focus → focī "at the hearth", "at the center of the community". In archaic times, the locative singular of third declension nouns was interchangeable between ablative and dative forms, but in the Augustan period, the use of the dative form became fixed.

Syncretism

Syncretism, where one form in a paradigm shares the ending of another form in the paradigm, is common in Latin. The following are the most notable patterns of syncretism:

Gender-specific

For pure Latin neuter nouns, the nominative singular, vocative singular, and accusative singular are identical; and the nominative plural, vocative plural, and accusative plural all end in -a. (Both of these features are inherited from Proto-Indo-European, so are not true syncretism as the case endings were never separate in the first place.)

Case-specific

The vocative form is the same as the nominative in both singular and plural, except for second declension masculine nouns ending in –us and a few nouns of Greek origin. For example, the vocative of Aeneās is Aenea, although Aeneās is first declension.

The genitive singular is the same as the nominative plural in first, second, and fourth declension masculine and feminine pure Latin nouns.

The dative singular is the same as the genitive singular in first and fifth declension pure Latin nouns.

The dative is always the same as the ablative in the plural, and in the singular in the second declension, the third declension full i-stems (i.e. neuter i-stems, adjectives), and fourth declension neuters.

The dative, ablative, and locative are identical in the plural.

The locative is identical to the ablative in the fourth and fifth declensions.

History of cases

Old Latin had essentially two patterns of endings. One pattern was shared by the first and second declensions, which derived from the Proto-Indo-European thematic declension. The other pattern was used by the third, fourth and fifth declensions, and derived from the athematic PIE declension.

Nouns

There are five declensions for Latin nouns:

First declension (a stems)

Nouns of this declension usually end in –a in the nominative singular and are mostly feminine, e.g. 'road' (via, viae f.) and 'water' (aqua, aquae fem.). There is a small class of masculine exceptions generally referring to occupations, e.g. 'poet' (poēta, poētae m.) and 'sailor' (nauta, nautae masc.).

The predominant letter in the ending forms of this declension is a. The nominative singular form consists of the stem and the ending –a, and the genitive singular form is the stem plus –ae.

The locative endings for the first declension are –ae (singular) and –īs (plural), similar to the genitive singular and ablative plural, as in mīlitiae "in war" and Athēnīs "at Athens".

First declension Greek nouns

The first declension also includes three types of Greek loanwords, derived from Ancient Greek's Alpha Declension. They are declined irregularly in the singular, but are sometimes treated as if they were native Latin nouns, e.g. nominative athlēta instead of the original athlētēs. Interestingly, archaic (Homeric) first declension Greek nouns and adjectives had been formed in exactly the same way as in Latin: nephelēgeréta Zeus (Zeus the cloud-gatherer) had in classical Greek become nephelēgerétēs.

For full paradigm tables and more detailed information, see the Wiktionary appendix First declension.

Second declension (o stems)

The second declension is a large group of nouns consisting of mostly masculine nouns like equus, equī ("horse") and puer, puerī ("boy") and neuter nouns like castellum, castellī ("fort"). There are several small groups of feminine exceptions, including names of gemstones, plants, trees, and some towns and cities.

In the nominative singular, most masculine nouns consist of the stem and the ending –us, although some end in –er, which is not necessarily attached to the complete stem. Neuter nouns generally have a nominative singular consisting of the stem and the ending –um. However, every second-declension noun has the ending –ī attached as a suffix to the root of the noun in the genitive singular form. The predominant letter in the ending forms of this declension is o.

The locative singular ending for the second-declension was -ī, like the genitive singular, as in Corinthī "at Corinth". The locative plural ending for the second-declension was -īs, like the ablative plural, as in Philippīs "at Philippi".

Nouns ending in –ius and –ium have a genitive singular in –ī in earlier Latin, which was regularized to –iī in the later language. Masculine nouns in –ius have a vocative singular in –ī at all stages. These forms in –ī are stressed on the same syllable as the nominative singular, sometimes in violation of the usual Latin stress rule. For example, the genitive and vocative singular Vergilī (from Vergilius) is pronounced [werˈɡiliː], with stress on the penult, even though it is short.

There is no contraction of –iī(s) in plural forms and in locative.

In the older language, nouns ending with –vus, –quus and –vum take o rather than u in the nominative and accusative singular. For example, servus, –ī ("slave") could be servos, accusative servom.

Second declension –r nouns

Some masculine nouns of the second declension end in –er or –ir in the nominative singular. For such nouns, the genitive singular must be learned to see if the e is dropped. For example, socer, –erī keeps its e. However, the noun magister, –trī ("teacher") drops its e in the genitive singular. Nouns with –ir in the nominative singular, such as triumvir, never drop the i.

The declension of second declension –r nouns is identical to that of the regular second declension, with the exception of the vocative singular, which is identical to the nominative rather than ending in –e.

For declension tables of second declension nouns, see the corresponding Wiktionary appendix.

Second declension Greek nouns

The second declension contains two types of masculine Greek nouns and one form of neuter Greek noun. These nouns are irregular only in the singular, as are their first declension counterparts. Greek nouns in the second declension are derived from the Omicron Declension.

Some Greek nouns may also be declined as normal Latin nouns. For example, theātron can appear as theātrum.

Irregular forms

The plural of deus (god, deity) is irregular, cf. Wiktionary: deus.
The vocative singular of deus is not attested in Classical Latin. In Ecclesiastical Latin the vocative of Deus (God) is Deus.

In poetry, –um may be substituted for –ōrum as the genitive plural ending.

Third declension (i and consonant stems)

The third declension is the largest group of nouns. The nominative singular of these nouns may end in –a,–e, –ī, –ō, –y, –c, –l, –n, –r, –s, –t, or –x. This group of nouns includes masculine, neuter, and feminine nouns. Examples are flumen, fluminis neut. ("river"), flos, floris masc. ("flower"), and pax, pacis fem. ("peace"). Each noun has the ending –is as a suffix attached to the root of the noun in the genitive singular form. Masculine, feminine and neuter nouns each have their own special nominative singular endings. For instance, many masculine nouns end in –or (amor). Many feminine nouns end in –īx (phoenīx), and many neuter nouns end in –us (onus, tempus) with an r stem in the oblique cases (gen. oneris, temporis).

¹ The nominative singular is formed in one of four ways: with –s, with no ending, or by one of these two with a different stem from the oblique cases. The same is true of other forms that are the same as the nominative singular: the vocative singular and the neuter accusative singular.

² The nominative and accusative of neuter nouns are always identical. It should not be assumed that –en is always the appropriate ending, as it might appear above.

The locative endings for the third declension were -ī or -e (singular) and -ibus (plural), as in rūrī "in the country" and Trallibus "at Tralles".

Third declension i-stem nouns

The third declension also has a set of nouns that are declined differently. They are called i-stems. i-stems are broken into two subcategories: pure and mixed. Pure i-stems are indicated by the parisyllabic rule or special neuter endings. Mixed i-stems are indicated by the double consonant rule.

Masculine and feminine

Parisyllabic rule: Some masculine and feminine third-declension i-stem nouns have the same number of syllables in the genitive as they do in the nominative. For example: amnis, –is. The nominative ends in –is. Double consonant rule: The rest of the masculine and feminine third-declension i-stem nouns have two consonants before the –is in the genitive singular. For example: pars, partis.

Neuter

Special neuter ending: Neuter third-declension i-stems have no rule. However, all of them end in –al, –ar or –e. For example: animal, –ālis. This can be remembered with the help of the mnemonic involving a pirate named Al: "Al, ar' e' going pirating today?"

Pure i-stems may exhibit peculiar endings in both singular and plural. Mixed i-stems employ normal (consonant) 3rd declension endings in the singular but i-stem endings in the plural. Note the alternative i-stem endings indicated in parentheses.

¹ The nominative singular is formed in one of four ways: with –s, with no ending, or by one of these two with a different stem from the oblique cases. The same is true of other forms that are the same as the nominative singular: the vocative singular and the neuter accusative singular.

The rules for determining i-stems from non-i-stems and "mixed" i-stems should be thought of more as "guidelines" than "rules": even among the Romans themselves, the categorization of a 3rd declension word as an i-stem or non-i-stem was quite fluid. The result is that many words that should be i-stems according to the parisyllabic and consonant stem rules actually are not, such as canis or iuvenis. By the parisyllabic rule, canis should be a masculine i-stem and thus differ from the non-i-stems by having an extra –i– in the plural genitive form: *canium. In reality, the plural genitive of canis is canum, the form of a non-i-stem. This fluidity even in Roman times results in much more uncertainty in Medieval Latin, as scholars were trying to imitate what was fluid to begin with.

Peculiarities

In the third declension, there are four irregular nouns.

¹ Rarely used.

² Rarely used in the dative case.

Fourth declension (u stems)

The fourth declension is a group of nouns consisting of mostly masculine words such as fluctus, fluctūs (masc.) ("a wave") and portus, portūs (masc.) ("a port") with a few feminine exceptions, including manus, manūs (fem.) ("hand"). The fourth declension also includes several neuter nouns including genu, genūs (neut.) ("knee"). Each noun has the ending –ūs as a suffix attached to the root of the noun in the genitive singular form. The predominant letter in the ending forms of this declension is u, but the declension is otherwise very similar to the third.

In the dative and ablative plural, –ibus is sometimes replaced with –ubus. This is so for only a few nouns, such as artūs (plurale tantum), "the limbs".

The declension of domus is declined like a full 4th declension, and also like the 2nd declension, except on the plural dative and ablative cases which are always domibus.

¹Also declined like in the 4th declension.

Fifth declension (e stems)

The fifth declension is a small group of nouns consisting of mostly feminine nouns like 'affair, matter, thing' (rēs, reī fem.) and 'day' (diēs, diēī usually masculine, except on notable days when it is feminine). Each noun has either the ending –ēī or –eī as a suffix attached to the root of the noun in the genitive singular form.

Note that nouns ending in –iēs have long ēī in the dative and genitive, while nouns ending in a consonant + –ēs have short eī in these cases.

The locative ending of the fifth declension was -ē (singular only), identical to the ablative singular, as in hodiē "today".

Personal pronouns

The first and second persons are irregular, and both pronouns are indeclinable for gender.

The genitive forms meī, tuī, nostrī, vestrī, suī are used as complements in certain grammatical constructions, whereas nostrum, vestrum are used in the partitive meaning. To express possession, the possessive pronouns (essentially adjectives) meus, tuus, noster, vester are used, declined in the 1st and 2nd declensions to agree in number and case with the thing possessed, e.g. pater meus "my father", māter mea "my mother". The vocative singular masculine of meus is mī: mī Attice "my dear Atticus".

Usually, to show the ablative of accompaniment, cum would be added to the ablative form. However, with personal pronouns (1st and 2nd person), the reflexive and the interrogative, cum is added onto the end of the ablative form. That is: mēcum "with me", nōbīscum "with us", tēcum "with you", vōbīscum, sēcum and quōcum (sometimes quīcum).

For the third person pronoun is "he", see below.

Reflexive pronoun (sē)

The third person reflexive pronoun always refers back to the subject, regardless of whether the subject is singular or plural:

This pronoun has a possessive adjective: suus, sua, suum, meaning "his/her own" or (if the subject is plural) "their own":

Patrem suum numquam vīderat. (Cicero) "He had never seen his father." (= his own father)

When "his" or "her" refers to someone else, not the subject, the genitive pronoun eius "of him" is used instead of suus:

Fit obviam Clodio ante fundum eius. (Cicero) "He met Clodius in front of the latter's farm."

When one sentence is embedded inside another with a different subject, se and suus can refer to either subject:

Patres conscripti ... legatos in Bithyniam miserunt qui ab rege peterent, ne inimicissimum suum secum haberet sibique dederet. "The senators ... sent ambassadors to Bithynia, who were to ask the king not to keep their greatest enemy with him but hand him over to them."

Demonstrative pronouns and adjectives

Relative, demonstrative and indefinite pronouns are generally declined like first and second declension adjectives, with the following differences:

the nominatives are often irregular

the genitive singular ends in –īus rather than –ae or –ī.

the dative singular ends in –ī: rather than –ae or –ō.

These differences characterize the "pronominal" declension, and a few special adjectives (tōtus "the whole", sōlus "alone", ūnus "one", nūllus "no", alius "another", alter "another (of two)", etc.) are also declined according to this pattern.

All demonstrative, relative, and indefinite pronouns in Latin can also be used adjectivally, with some small differences; for example in the interrogative pronoun, quis "who?" and quid? "what?" are usually used for the pronominal form, quī and quod "which?" for the adjectival form.

Third person pronoun

The weak demonstrative pronoun is, ea, id "that" also serves as the 3rd person pronoun "he, she, it":

This pronoun is also often used adjectivally, e.g. is homo "that man", ea pecunia "that money". It has no possessive adjective; the genitive is used instead: pater eius = "his/her father"; pater eōrum = "their father".

Declension of īdem

The pronoun or pronominal adjective īdem, eadem, idem means 'the same'. It is derived from is with the suffix -dem. However, some forms have been assimilated.

Other demonstrative pronouns

Similar in declension to ille is the pronoun iste, ista, istud "that one of yours", and alius, alia, aliud "another".

Interrogative pronouns

The interrogative pronouns are used strictly for asking questions. They are distinct from the relative pronoun and the interrogative adjective (which is declined like the relative pronoun). Interrogative pronouns rarely occur in the plural. The plural interrogative pronouns are the same as the plural relative pronouns.

Correlatives

Correlatives are the corresponding demonstrative, relative, interrogative, and indefinite forms of pronouns, pronominal adjectives, and adverbs. These are shown below:

First and second declension adjectives

First and second declension are inflected in the masculine, the feminine and the neuter; the masculine form typically ends in –us (although some end in –er, see below), the feminine form ends in –a, and the neuter form ends in –um. Therefore, some adjectives are given like altus, alta, altum.

First and second declension –r adjectives

Some first and second declension adjectives' masculine form end in –er. As with second declension –r nouns, some adjectives retain the e throughout inflection, and some omit it. Sacer, sacra, sacrum omits its e while miser, misera, miserum keeps it.

First and second –īus genitive adjectives

Nine first and second declension adjectives are irregular in the genitive and the dative in all genders. They can be remembered by using the mnemonic acronym VNVS NAVTA. They are:

ūllus, –a, –um; any
nūllus, –a, –um; no, none (of any)
uter, –tra, –trum; which (of two)
sōlus, –a, –um; sole, alone
neuter, –tra, –trum; neither (of two)
alius, –a, –ud; (gen. sing. alīus, often replaced by alterīus; another)
ūnus, –a, –um; one
tōtus, –a, –um; whole
alter, –era, –erum; the other (of two)

Third declension adjectives

Third declension adjectives are normally declined like third declension i-stem nouns, except for the fact they always have –ī rather than –e in the ablative singular (unlike i-stem nouns, in which only neuters have –ī). Some adjectives, however, like the one-ending vetus, veteris (old, aged), have –e in the ablative singular (all genders), –um in the genitive plural (all genders), and –a in the nominative and accusative plural (neuter only).

Third declension adjectives with one ending

These have a single nominative ending for all genders, although as usual the endings for the other cases vary. As with nouns, a genitive is given for the purpose of showing the inflection.

Third declension adjectives with two endings

Third declension adjectives that have two endings have one form for the masculine and feminine, and a separate form for the neuter. The ending for the masculine and feminine is –is, and the ending for the neuter is –e. It is not necessary to give the genitive, as it is the same as the nominative m.sg.

Third declension adjectives with three endings

Third declension adjectives with three endings have three separate nominative forms for all three genders. Like third and second declension –r nouns, the masculine ends in –er. The feminine ends in –ris, and the neuter ends in –re. The genitive is the same as the nominative f.sg.

Comparative and superlative forms of adjectives

As in English, adjectives have superlative and comparative forms. For regular first and second declension and third declension adjectives with one or two endings, the comparative is formed by adding –ior for the masculine and feminine, and –ius for the neuter to the base. The genitive for both are formed by adding –iōris. Therefore, they are declined like the third declension. However, they are not declined as i-stems are. Superlatives formed by adding –issimus, –a, –um to the base. Now, we find that superlatives are declined like first and second declension adjectives.

Comparatives and superlatives of –er adjectives

Adjectives (in the third and first and second declensions) that have masculine nominative singular forms ending in –er have different forms. If the feminine and neuter forms drop the e, use that for the comparative form. The superlative is formed by adding –rimus onto the masculine form.

Comparatives and superlatives of –lis adjectives

Some third declension adjectives with two endings in –lis in the sexed nominative singular have irregular superlative forms. The following are the only adjectives that have this unique form.

Irregular comparatives and superlatives

As in most languages, Latin has adjectives that have irregular comparatives and superlatives.

1: noun used with genitive to express more of something. In the plural used as an adjective: plūrēs, plūra, genitive plūrium

2: often replaced by the regular form maturissimus, –a, –um

3: indeclinable

Declension of numerals

There are several different kinds of numeral words in Latin: the two most common are cardinal numerals, and ordinal numerals. There are also several more rare numerals, e.g., distributive numerals and adverbial numerals.

Cardinal numerals

All cardinal numerals are indeclinable, except by ūnus (one), duo (two), trēs (three), hundreds from 200 - 900 (like ducentī, trecentī, quadringentī, etc.) and mīlia (thousands), which have cases and genders like adjectives. Ūnus, ūna, ūnum is declined like a 1st and 2nd declension pronoun with –īus in the genitive, and –ī in the dative. Duo is declined irregularly, tria is declined like a 3rd declension plural adjective, -centī (hundred) numerals decline like 1st and 2nd declension adjectives, and mīlia is declined like a 3rd declension i-stem neuter noun:

The existence of plural endings for ūnus might seem unnecessary; however, they are used with pluralia tantum nouns, e. g. ūna castra (one [military] camp), ūnae scālae (one ladder).

The word ambō, "both", is declined like duo except that its o is long. Both declensions derive from the Indo-European dual number, otherwise defunct in Latin, rather than the plural.

The numeral centum (one hundred) is indeclinable, but all the other hundred numerals are declinable.

The word mīlle "a thousand" is a singular and indeclinable adjective. However, its plural, mīlia, is a plural 3rd declension i-stem neuter noun. To write the phrase "four thousand horses" in Latin, the genitive is used: quattuor mīlia equōrum, literally, "four thousands of horses".

The rest of the numbers are indeclinable whether used as adjectives or as substantives.

The conjunction et between numerals can be omitted: vigintī ūnus, centum ūnus. Et is not used when there are more than two words in a compound numeral: centum trīgintā quattuor. The word order in the numerals from 21 to 99 may be inverted: ūnus et vigintī. Numbers ending in 8 or 9 are usually named in subtractive manner: duodētrīgintā, ūndēquadrāgintā.

Ordinal numerals

Ordinal numerals all decline like normal 1st and 2nd declension adjectives. When declining the two-word ordinals (thirteenth through twenty-second, with the exception of twentieth), both words decline to match in gender, number and case.

prīmus first

secundus second

tertius third

vicensimus/vicēsimus twentieth

Note: secundus only means "second" in the sense of "following". The adjective alter, –ra, –rum meaning "the other (of two)" was more frequently used in many instances that English would use "second".

Ordinal numbers, not cardinal numbers, are commonly used to represent dates, because they are in the format of "in the tenth year of Caesar", etc. which also carried over into the anno Domini system and Christian dating, e.g. annō post Christum nātum centēsimō for AD 100.

Numerals for plurals with singular meaning

Certain nouns in Latin were plural, but had singular meaning, for example litterae "a letter", castra "a camp", catēnae "a set of chains", vestīmenta "a set of clothes", hibernae "winter quarters", nūptiae "a wedding", quadrīgae "a four-horse chariot" etc. A special series of numeral adjectives was used for counting these, namely ūnī, bīnī, trīnī, quadrīnī, quīnī, sēnī, and so on. Thus Roman authors would write: ūnae litterae "one letter", trīnae litterae "three letters", quīna castra "five camps" etc.

Distributive numerals

Another set of numeral adjectives, similar to the above but differing in the adjectives for 1, 3, and 4, were the distributive numerals: singulī, bīnī, ternī, quaternī, quīnī, sēnī... The meaning of these was "one each", "two each" (or "in pairs"), etc., for example ibī turrīs cum ternīs tabulātīs ērigēbat "there he began erecting towers with three storeys each" (Caesar); bīnī senātōrēs singulīs cohortibus praepositī "a pair of senators was put in charge of each group of soldiers" (Livy).

Adverbial numerals

Adverbial numerals are (as the name states) indeclinable adverbs, but because all of the other numeral constructions are adjectives, they are listed here with them. Adverbial numerals give how many times a thing happened. semel = once, bis = twice, ter = thrice (three times), quater = four times, and so on.

The suffix -iēns may also be spelled -iēs: quinquiēs, sexiēs, etc.

Multiplicative numerals

Multiplicative numerals are declinable adjectives. They give how many times a thing is. simplex = simple, duplex = double, triplex = triple, quadruplex = fourfold, and so on.

Proportional numerals

Proportional numerals are declinable adjectives. simplus = simple, duplus = twice as great, triplus = thrice as great, quadruplus = four times as great, and so on.

Temporal numerals

Temporal numerals are indeclinable adverbs. ūniennis= in (a period of) one year, of one year; biennis = in (a period of) two years, of two years; triennis = in (a period of) three years, of three years; quadriennis = in (a period of) four years, of four years; and so on.

Partitive numerals

Partitive are declinable adjectives. ūninarius= of one part, binarius = of two parts, ternarius = of three parts, quaternarius = of four parts, and so on.

Adverbs and their comparatives and superlatives

Adverbs are not declined. However, adverbs must be formed if one wants to make an adjective into an adverb.

Adverbs from first and second declension adjectives

First and second declension adjectives' adverbs are formed by adding –ē onto their bases.

Adverbs from third declension adjectives

Typically, third declension adjectives' adverbs are formed by adding –iter onto their bases. However, most third declension adjectives with one ending simply add –er to their bases.

Comparative and superlative of adverbs

Adverbs' comparative forms are their neuter adjectives' comparative forms. Adverbs' superlative forms are made in the same way in which first and second declension adjectives' adverbs are made.

First and second declension adjectives' adverbs are formed by adding –ē onto their bases.

Irregular adverbs and their comparative and superlative forms

As so with adjectives, there are irregular adverbs with peculiar comparative and superlative forms.

Irregularity in number

Some nouns are only used in the singular (singulare tantum) such as:

Materials such as aurum (gold) and aes (copper)

Abstract nouns such as celeritās (speed) and scientia (knowledge)

Some nouns are only used in the plural (plurale tantum) such as:

Many festivals, such as Saturnalia

Castra (camp) and arma (arms)

A few geographical names are plural such as Thēbae (Thebes).

Indeclinable nouns

Indeclinable nouns are nouns which only have one form in all cases (of the singular).

fās — fate, divine law

īnstar — likeness

māne — morning

nefās — sin, abomination

nihil / nil — nothing, none

secus – sex

Heterogeneous nouns

Heterogeneous nouns are nouns which vary in respect to gender.

A few nouns in the second declension occur in both the neuter and masculine. However, their meanings remain the same.

Some nouns are one gender in the singular, but become another gender in the plural. They may also change in meaning.

Order of the cases

In modern textbooks of Latin, there is no single international standard for the sequence of cases.

Nom–(Voc)–Acc–Gen–Dat–Abl–(Loc)

This order reflects the syncretic trends of different cases to share similar endings. Usually the vocative and locative cases are omitted because they appear in the paradigm of only a few word classes and are dealt with separately. This makes the paradigm appear normally in the format Nom–Acc–Gen–Dat–Abl, which is also roughly the order of how frequently the cases appear in Latin text, meaning that the cases are introduced in teaching in this order. This paradigm has been the usual order in the United Kingdom and many Commonwealth countries since the publication of Benjamin Hall Kennedy's Latin Primer (1866). It is the only method nowadays used in Hungary and Finland. It is also usual in France, Spain, and Portugal.

Nom–Gen–Dat–Acc–(Voc)-Abl–(Loc)

This alternate sequence arose from Byzantine grammarians who were originally writing about Greek. It is standard in the United States, although modern texts increasingly move the vocative at the end to minimize disruption to the declensions in which it is identical to the nominative; some introductory texts such as Wheelock's Latin almost entirely ignore the vocative and locative except for a few brief notes, giving the format Nom–Gen–Dat–Acc–Abl-(Voc). This paradigm is also used in Poland, as it closely corresponds to the conventional case order in the Polish language, except for the latter's use of an instrumental case instead of an ablative. The same sequence is predominant in the Netherlands, although the modern Dutch language has largely lost its case system; instead, the rationale is that this general order is convenient for the consistent teaching of three different commonly studied declensive languages: Latin, Ancient Greek, and modern German. The order Nom–Gen–Dat–Acc–(Voc)–Abl is also used in Germany itself to echo the conventional order of German cases (Nom–Gen–Dat–Acc), and also in Lithuania because the conventional order of Lithuanian noun cases is the same. The locative is dealt with separately as it is seldom used in Latin and might be considered to be on the verge of extinction in Classical Latin.

The order Nom–Gen–Dat–Acc–Voc–Abl is the standard order used in Greece (both for the teaching of Ancient and Modern Greek as well as Latin) and Italy (with the vocative case before the ablative). Here again, the locative is dealt with separately in the courses.

Others

Brazilian grammarian Napoleão Mendes used the unusual sequence Nom–Voc–Gen–Dat–Abl–Acc. The Latinum podcast uses Nom–Voc–Acc–Abl–Dat–Gen, as this facilitates memorisation. Latinum deals with the locative separately.