hyponyymia

Hyponymia is a term used in linguistics to describe a semantic relation in which the meaning of one word is included in the meaning of another. This relation is commonly called hyponymy: a hyponym is a more specific term whose extension is a subset of its hypernym. The word hyponymia may be used to refer to either the property of a word that participates in hyponymy or, more broadly, to the system of hyponymic relations within a language or lexicon. In lexical databases and linguistic theory, hyponymy organizes vocabularies into hierarchies, with hypernyms at higher levels and hyponyms at lower levels. Examples include dog as a hyponym of animal, poodle as a hyponym of dog, and car as a hyponym of vehicle. Hyponymy is distinct from meronymy (part–whole) and from synonymy (same meaning). The term hyponymia, therefore, can refer to the set of hyponymic relations that exist in a given language, or to the state of a particular term as a hyponym within that system. In practice, researchers describe hyponymic networks using resources such as WordNet, which encodes many such relations to support semantic tasks in information retrieval and natural language understanding.