Wikipedia Reference Information
Lexicology (from lexiko-, in Late Greek lexikon) is that part of linguistics that deals with the study of words, the relations between words (i.e. semantical relations), and the whole lexicon. The term first appeared in the 1820s, though there were lexicologists before that. Computational lexicology is a related field (in the same way that computational linguistics is related to linguistics) that deals with the computational study of dictionaries and their contents. An allied science to lexicology is lexicography, which also deals with words but only when they have to do something with dictionaries, and the lexicon included in them. Lexicography is the theory and practice of composing dictionaries. Sometimes lexicography is considered a part or a branch of lexicology, though they should not be mistaken (lexicographers are those people who write the dictionaries, they are lexicologists, but not all lexicologists are lexicographers)! It is said that lexicography is the practical lexicology, it is practically oriented though it has its own theory, while the pure lexicology is mainly theoretical.
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