a word which has two opposite meanings
Origin and usage
The noun contronym (or contranym) is formed from the prefix contra- and the suffix -onym. It has been used since the early 1960s.
A contronym is a word that can have two opposite or highly contrasting meanings: for example ‘cleave’ can mean both cut or break, and cling to, while ‘oversight’ can mean both something accidentally omitted and close control. Contronym was added to the crowdsourced Open Dictionary in 2017. It is one of a number of terms for different kinds of words ending in -onym; you can find a list that includes several of them here. Another term for contronym is ‘Janus word’. Janus was the Roman god of gates and doorways and is usually depicted with two faces, so that he can look both ways. Another expression that uses his name is Janus-faced, a synonym for ‘two-faced‘ added to the Open Dictionary back in 2011. Janus is also at the root of the month of January, because as well as being the god of doorways he was the god of beginnings, and therefore an appropriate deity to preside over the first month of the year.
“I prefer to see myself as the Janus, the two-faced god who is half Pollyanna and half Cassandra, warning of the future and perhaps living too much in the past—a combination of both.”
antonym, capitonym, demonym, eponym