Lexicon - Size and Organization

Size and Organization

Items in the lexicon are called lexemes or word forms. Lexemes are not atomic elements but contain both phonological and morphological components. When describing the lexicon a reductionist approach is used, trying to remain general while using a minimal description. To describe the size of a lexicon, lexemes are grouped into lemmas. A lemma is a group of lexemes generated by inflectional morphology. Lemmas are represented in dictionaries by headwords which list the citation forms and any irregular forms, since these must be learned to use the words correctly. Lexemes derived from a word by derivation morphology are considered new lemmas. The lexicon is also organized according to open and closed categories. Closed categories, such as determiners or pronouns, rarely get new lexemes and their function is primarily syntactic. Open categories such as nouns and verbs have highly active generation mechanisms and their lexemes are more semantic in nature.