cohyponyms

Cohyponyms are lexical items that share a common hypernym and are each hyponyms of that broader term. In other words, two words are cohyponyms if they belong to the same higher-level category and denote distinct, more specific members of that category. This relationship is typically considered symmetric: if A and B are cohyponyms under H, both are hyponyms of H.

Examples illustrate the idea: car and bicycle are cohyponyms under vehicle; apple and orange are cohyponyms under fruit; violin and flute are cohyponyms under musical instrument. Cohyponyms are not synonyms; they have related but distinct meanings and describe different members of a shared category. The existence of multiple senses can complicate the relation if the words acquire different hypernyms in different contexts, a phenomenon known as polysemy.

Applications of cohyponymy appear in lexical semantics, thesaurus construction, and natural language processing. Identifying cohyponyms helps map semantic fields, measure semantic similarity, and organize lexical databases. It also supports tasks such as word sense disambiguation and hierarchical clustering of terms. Limitations include imprecise borders between categories, varying granularity across domains, and sense-specific hypernyms that can obscure straightforward cohyponym relations.

In summary, cohyponyms are siblings in a semantic taxonomy: words that share a common hypernym and refer to distinct items within that higher-level class. See also hypernym, hyponym, semantic field, and taxonomy.