lexicon (n.)

In its most general sense, the term is synonymous with VOCABULARY. A dictionary can be seen as a set of lexical ENTRIES. The lexicon has a special status in GENERATIVE GRAMMAR, where it refers to the COMPONENT containing all the information about the STRUCTURAL properties of the LEXICAL ITEMS in a LANGUAGE, i.e. their specification SEMANTICALLY, SYNTACTICALLY and PHONOLOGICALLY. In later MODELS, these properties are formalized as FEATURES, and put in square brackets; e.g., WORD-CLASS assignments include NOUN [+N], etc. Given this component, the TERMINAL symbols in PHRASE-MARKERS can then be related directly to the lexicon through the use of lexical TRANSFORMATIONS; e.g. any item in the lexicon specified by [+D] can be attached to the NODE D, and so on. The role of the lexicon became central in LEXICAL-FUNCTIONAL GRAMMAR and HEAD-DRIVEN PHRASE-STRUCTURE GRAMMAR. The mental lexicon is the stored mental representation of what we know about the lexical items in our language.