early 14c., "feeling of disgust, hatred, loathing," from O.Fr. abomination, from L. abominationem (nom. abominatio) "abomination," from abominatus, pp. of abominari "shun as an ill omen," from ab- "off, away from" + omin-, stem of omen (see omen). Meaning intensified by folk etymology derivation from L. ab homine "away from man," thus "beastly."