abhorrent (adj.)

c. 1400, "to loathe, regard with repugnance, dislike intensely," literally "to shrink back with horror or dread," from Latin abhorrere "shrink back from, have an aversion for, shudder at," from ab "off, away from" (see ab-) + horrere "tremble at, shudder," literally "to bristle, be shaggy," from PIE *ghers- "start out, stand out, rise to a point, bristle" (see horror).

Formerly also "fill (someone) with horror or loathing" (16c.). In Latin it was less intense: "be remote from, vary from, differ from, be out of harmony with." Related: Abhorred; abhorring.

"feeling of extreme aversion or detestation," 1650s; see abhorrent + -ence. OED recommends this form for "act or fact of abhorring," abhorrency (c. 1600) for "quality of being abhorrent."