Words That Are Their Own Opposites (2015)

I ran into "The payment was remitted" at work, and I wasn't sure initially if they said they were denying to reimburse me, or if it the payment had been sent out.

Weirdly, the verb "to doubt" used to be used in the opposite sense to how it is now. So, for instance, if you say "I doubt it's going to rain", that means you think it won't rain. But a few hundred years ago, it would have meant you think it is going to rain. (And of course if you lived in England, you'd probably have been right.)

If you've read Gibbon's The Decline and the Fall of the Roman Empire you will have wondered at the meaning of both sensible and insensible which both seem to alternate between opposites randomly throughout the book.

If we take archaic usage into account, there are many more words that now mean the opposite of what they used to mean, e.g. “awesome”.

these are called "Janus words" or self-antonyms. Such as "flammable" and "inflammable".

https://en.wikipedia.org/wiki/Auto-antonym

Buckle — to collapse, or to fasten

Raze/Raise might be a “phonetic contranym”

im wondering how an AI would deal with this sort of thing. would contronym strings, be like forbidden ASCII?

Inflammable?

Reciprocal