| Horseback 1. (n.) The back of a horse. 2. (n.) An extended ridge of sand, gravel, and boulders, in a half-stratified condition. Thesaurus Entries across, astraddle, astride, by horse, chine, col, comb, esker, hogback, kame, mounted, on, on horseback, ridge, saddle, saddleback, spine, straddle, straddle-legged, straddleback | ![]() |