Antilogy [an.til.uh.jee] noun: a word whose secondary meaning is the opposite of its primary meaning
In every language some words have a secondary meaning that is the opposite of their primary one. For instance, a sanction, both in English and French, is a form of opposition or punishment, as in economic sanctions, but also permission or even blessing, as of a marriage. The Arabs in their devotion to language have a term for such words: addad. For lack of one in English, in writing about them I have settled on antilogy. more