An antagonym is another word for a contranym, a single word with two opposing meanings - such as "fast", meaning, "quick" or "unmoving".
It is a contranym AKA antagonym AKA autoantonym
A contronym or antagonym is a word that is also it's opposite. For example, Clip can mean "to bind together" or "to separate" Screen can mean 'to show' (a movie) or 'to hide' Cleave can mean to split or to adhere.
A contronym or antagonym is a word that is also it's opposite. For example, Clip can mean "to bind together" or "to separate" Screen can mean 'to show' (a movie) or 'to hide' Cleave can mean to split or to adhere.