"extreme dislike, hatred, abhorrence, loathing," early 15c., detestacioun, from Old French detestation (14c.) and directly from Latin detestationem (nominative detestatio) "execration, detestation," noun of action from past-participle stem of detestari "to curse, execrate, abominate, express abhorrence for," literally "denounce with one's testimony," from de "from, down" (see de-) + testari "be a witness," from testis "witness" (see testament).
