autoantonym

noun

au·​to·​an·​to·​nym ˌȯ-(ˌ)tō-ˈan-tə-ˌnim 

plural autoantonyms

: contronym

I loved "perspicacious" and "recondite" and "hortatory" and "cleave," the last of which meant the opposite of itself, both to join and to tear apart. "Impregnable" was an autoantonym, too. It was like a snake that ate its own tail.

—Joshua Henkin, New York Times, 25 Aug. 2013

Word History

First Known Use

1983, in the meaning defined above

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