Polisemi

Polisemi (polysemy) is a linguistic phenomenon in which a single word form has multiple related meanings. This contrasts with homonymy, where different senses arise from distinct origins and are not semantically linked. Polysemy is common across languages and is a central topic in lexical semantics and lexicography.

The term polysemy derives from Greek roots polys "many" and sēma "sign." In many languages the cognate term polisemi is used to describe the same phenomenon. In dictionaries, a single entry may list several senses that are semantically related, sometimes with notes about their relationships.

Polysemy emerges through semantic extension. Metaphor stretches a word from a concrete domain to new domains (for example, head used for the body part and for a leader). Metonymy and generalization can also create related senses as a word shifts to cover related concepts.

Examples include head, with senses meaning the upper part of the body and the person in charge of an organization; and foot, meaning the bottom part of the body and the base of a natural or man-made object such as the foot of a mountain or a page.

Understanding polysemy is important for language processing, lexicography, and natural language understanding, including computational applications. It is distinguished from homonymy by the semantic relatedness of its senses rather than their etymological origin.