In linguistics, homonyms, broadly defined, are words that are homographs (words that share the same spelling, regardless of pronunciation) or homophones (words that share the same pronunciation, regardless of spelling), or both. For example, according to this definition, the words row (propel with oars) and row (a linear arrangement) are homonyms, as are the words see (vision) and sea (body of water).

Homonymy can lead to communicative conflicts and thus trigger lexical (onomasiological) change. This is known as 'homonymic conflict'.

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