In linguistics, feminization has two mutually independent meanings.
First, it refers to the process of re-classifying nouns and adjectives which as such refer to male beings, including occupational terms, as feminine. This is done most of the time by adding inflectional suffixes denoting a female (such as the standard suffix -ess in English, and its equivalent -a in Spanish).
In some languages with grammatical gender, for example Dutch, there is a certain tendency to assign the feminine gender to – in particular abstract – nouns which are originally masculine or neuter. This also happened to some words in Middle English (which, in contrast to Modern English, had grammatical gender) which denoted virtue and vice. In Modern English, in spite of being this a gender-neutral language, some nonhuman things which are usually neuter are still sometimes feminized as a figure of speech, especially countries and ships (see also Gender in English § Ships, Gender in English § Modern English).