Lexicon

A lexicon is a list of words together with additional word-specific information, i.e. a dictionary.

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In linguistics, a lexicon has a slightly more specialized definition, as it 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 such that we get 'read-able' but not '*cry-able'.

Furthermore an individual lexical knowledge (or lexical concept) is a term used in academia to refer to an individual's vocabulary knowledge.