GUIDON, a sort of flag or standard borne by the king's life-guard; being broad at one extremity, almost pointed at the other, and slit or divided into two parts. The guidon is the ensign or flag of a troop of horse-guards.
GUIDON also denotes the officer who bears the guidon. The guidon is in the horse-guards what the ensign is in the foot. The guidon of a troop of horse takes place next below the cornet.