1530s, from Latin exhilaratus "cheerful, merry," past participle of exhilarare "gladden, cheer," from ex- "thoroughly" (see ex-) + hilarare "make cheerful," from hilarus "cheerful" (see hilarity). Related: Exhilarated; exhilarating.[exhilarate etymology, exhilarate origin, 英语词源]