lexicon

n. dictionary; vocabulary used in a particular profession, terminology; total number of morphemes within a language

Lexicon is also a synonym for dictionary or encyclopedic dictionary. For other uses, see lexicon (disambiguation). In linguistics, the lexicon of a language is its vocabulary, including its words and expressions. More formally, it is a language's inventory of lexemes.The lexicon includes the lexemes used to actualize words. Lexemes are formed according to morpho-syntactic rules and express sememes. In this sense, a lexicon organizes the mental vocabulary in a speaker's mind: First, it organizes the vocabulary of a language according to certain principles (for instance, all verbs of motion may be linked in a lexical network) and second, it contains a generative device producing (new) simple and complex words according to certain lexical rules. For example, the suffix '-able' can be added to transitive verbs only, so that we get 'read-able' but not '*cry-able'.
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Noun
1. a language user's knowledge of words
(synonym) vocabulary, mental lexicon
(hypernym) cognition, knowledge, noesis
(part-holonym) language, speech
2. a reference book containing an alphabetical list of words with information about them
(synonym) dictionary
(hypernym) wordbook
(hyponym) bilingual dictionary
(part-meronym) lexical entry, dictionary entry

n. lexicon, dictionary; vocabulary used in a particular profession, terminology; total number of morphemes within a language

n. lexicon