一词多义是指一个词语能表达多种意义。一词多义有时是因该词为多义词，有时则是用户有意误导。

• 小明走了一天了

「走」可解作「走路」或「离开」。

• 巴豆不可轻用

「轻用」可解作「使用低剂量」或「轻易使用」。

• 阿嬷，你要哪片音乐光盘？我烧给你。

「烧」可解作「刻录」或「烧给阿嬷」。

Polysemy (/pəˈlɪsᵻmi/ or /ˈpɒlᵻsiːmi/; 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. It is thus usually regarded as distinct from homonymy, in which the multiple meanings of a word may be unconnected or unrelated.