Polysemy (/pəˈlɪsɪmi/ or /ˈpɒlɪsiːmi/; from Greek: πολυ-, poly-, "many" and σῆμα, sêma, "sign") is the capacity for a sign (such as a word, phrase, or symbol) to have multiple meanings (that is, multiple semes or sememes and thus multiple senses), usually related by contiguity of meaning within a semantic field. Polysemy is thus distinct from homonymy—or homophony—which is an accidental similarity between two words (such as bear the animal, and the verb to bear); while homonymy is often a mere linguistic coincidence, polysemy is not.
Charles Fillmore and Beryl Atkins' definition stipulates three elements: (i) the various senses of a polysemous word have a central origin, (ii) the links between these senses form a network, and (iii) understanding the 'inner' one contributes to understanding of the 'outer' one.