Auto-antonym

An auto-antonym or autantonym, also called a contronym or antagonym among other terms, is a word with multiple meanings (senses) of which one is the reverse of another. For example, the word cleave can mean "to cut apart" or "to bind together". This phenomenon is called enantiosemy, enantionymy (enantio- means "opposite"), antilogy or autantonymy. An enantiosemic term is necessarily polysemic. An auto-antonym is alternatively called an antagonym, contronym, contranym, enantiodrome, enantionym, Janus word (after the Roman god Janus, who is usually depicted with two faces), self-antonym, antilogy, or addad (Arabic, singular didd). Some pairs of contronyms are true homographs, i.e., distinct words with different etymology which happen to have the same form. For instance cleave "separate" is from Old English clēofan, while cleave "adhere" is from Old English clifian, which was pronounced differently. Other contronyms are a form of polysemy, but where a single word acquires different and ultimately opposite definitions. For example, sanction—"permit" or "penalize"; bolt (originally from crossbows)—"leave quickly" or "fix/immobilize"; fast—"moving rapidly" or "fixed in place". Some English examples result from nouns being verbed in the patterns of "add to" and "remove from"; e.g. dust, seed, stone. Denotations and connotations can drift or branch over centuries. An apocryphal story relates how Charles II (or sometimes Queen Anne) described St Paul's Cathedral (using contemporaneous English) as "awful, pompous, and artificial," with the meaning (rendered in modern English) of "awe-inspiring, majestic, and ingeniously designed". "Literally" has had a literal meaning of "word for word", but its increasing use as a intensifier in colloquial speech can make it express "not literally but with emphasis". Negative words such as bad and sick sometimes acquire ironic senses by antiphrasis referring to traits that are impressive and admired, if not necessarily positive (that outfit is bad as hell; lyrics full of sick burns).