Лексикон: словарный состав языка и лингвистические аспекты.

Vocabulary of a language or branch of knowledge
the linguistic concept
A lexicon (plural: lexicons, rarely lexica) is the vocabulary of a language or branch of knowledge (such as nautical or medical). In linguistics, a lexicon is a language's inventory of lexemes. The word lexicon derives from Greek word λεξικόν (lexikon), neuter of λεξικός (lexikos) meaning 'of or for words'. Linguistic theories generally regard human languages as consisting of two parts: a lexicon, essentially a catalogue of a language's words (its wordstock); and a grammar, a system of rules which allow for the combination of those words into meaningful sentences. The lexicon is also thought to include bound morphemes, which cannot stand alone as words (such as most affixes). In some analyses, compound words and certain classes of idiomatic expressions, collocations and other phrases are also considered to be part of the lexicon. Dictionaries are lists of the lexicon, in alphabetical order, of a given language; usually, however, bound morphemes are not included.

Items in the lexicon are called lexemes, lexical items, 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 that list the citation forms and any irregular forms, since these must be learned to use the words correctly. Lexemes derived from a word by derivational morphology are considered new lemmas. The lexicon is also organized according to open and closed categories. Closed categories, such as determiners or pronouns, are rarely given new lexemes; 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.

Neologisms are new lexeme candidates which, if they gain wide usage over time, become part of a language's lexicon. Neologisms are often introduced by children who produce erroneous forms by mistake. Other common sources are slang and advertising.

Another mechanism involves generative devices that combine morphemes according to a language's rules. For example, the suffix " able" is usually only added to transitive verbs, as in "readable" but not "cryable".

A compound word is a lexeme composed of several established lexemes, whose semantics is not the sum of that of their constituents. They can be interpreted through analogy, common sense and, most commonly, context. Compounding is the most common of word formation strategies cross linguistically.

Comparative historical linguistics studies the evolution of languages and takes a diachronic view of the lexicon. The evolution of lexicons in different languages occurs through a parallel mechanism. Over time historical forces work to shape the lexicon, making it simpler to acquire and often creating an illusion of great regularity in language. Phonological assimilation, the modification of loanwords to fit a new language's sound structure more effectively. If, however, a loanword sounds too "foreign", inflection or derivation rules may not be able to transform it. Analogy, where new words undergo inflection and derivation analogous to that of words with a similar sound structure. Emphasis, the modification of words' stress or accent. Metaphor, a form of semantic extension.

The term "lexicon" is generally used in the context of a single language. Therefore, multi lingual speakers are generally thought to have multiple lexicons. Speakers of language variants (Brazilian Portuguese and European Portuguese, for example) may be considered to possess a single lexicon. Thus a cash dispenser (British English) as well as an automatic teller machine or ATM in American English would be understood by both American and British speakers, despite each group using different dialects. When linguists study a lexicon, they consider such things as what constitutes a word; the word/concept relationship; lexical access and lexical access failure; how a word's phonology, syntax, and meaning intersect; the morphology word relationship; vocabulary structure within a given language; language use (pragmatics); language acquisition; the history and evolution of words (etymology); and the relationships between words, often studied within philosophy of language. Various models of how lexicons are organized and how words are retrieved have been proposed in psycholinguistics, neurolinguistics and computational linguistics.