A lexical database is a lexical resource which has an associated software environment database which permits access to its contents. The database may be custom-designed for the lexical information or a general-purpose database into which lexical information has been entered.
Information typically stored in a lexical database includes lexical category and synonyms of words, as well as semantic and phonological relations between different words or sets of words.
References
Lexical database Wikipedia(Text) CC BY-SA