Pronunciation: (un-hôrs'), [key]
—v.t., -horsed, -hors•ing.
1. to cause to fall from a horse, as in battle; dislodge from the saddle: Sir Gawain unhorsed the strange knight.
2. to defeat; overcome; dislodge, as from a position or office: His vigorous campaign unhorsed his adversary.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.