Lexicology

Lexicology is a branch of linguistics that studies the vocabulary of a language, including the form, meaning, and use of words and fixed expressions. It examines the organization of the lexicon, the inventory of lexical items, and how words relate to one another within semantic networks. Unlike lexicography, which focuses on compiling and editing dictionaries, lexicology is theoretical and descriptive, concerned with how words exist and change in a language over time. The field covers morphology, semantics, and etymology, and often intersects with sociolinguistics and cognitive linguistics.

Key concepts include the distinction between lexemes and their inflected or derived forms, the study of polysemy and sense relations (synonymy, antonymy, hypernymy), and the analysis of collocations and idioms. Lexicologists analyze word formation processes—derivation, compounding, clipping, conversion—and track semantic shift across periods (e.g., broadening, narrowing, metaphorical extension). Etymology traces the historical origins of words and their path between languages, while loanword studies examine contact-induced vocabulary change.

Methodologically, lexicology relies on corpora, dictionaries, etymological sources, and lexical databases. Comparative and historical lexicology looks at vocabulary change across languages and time, while synchronic lexicology focuses on a single moment. Researchers may employ semantic field analysis, semantic networks, or word-frequency data to understand patterns of usage and meaning.

Applications include lexicography (descriptive and historical dictionaries), language teaching and learning, lexicographic data engineering, and natural language processing, where lexical resources underpin tasks such as parsing, word sense disambiguation, and semantic similarity evaluation.