means A word that shares its spelling or pronunciation with another but carries an entirely different meaning, like 'bat' the animal and 'bat' the stick.

from From Greek 'homos' (same) and 'onyma' (name) — literally 'same name.' That 'onyma' is the same root hiding inside 'synonym,' 'antonym,' and 'pseudonym,' a busy little Greek word for 'name' that English borrowed again and again. The term arrived in English in the 17th century via Latin 'homonymus,' built straight from the Greek pieces.