Flanker n. One who, or that which, flanks, as a skirmisher or a body of troops sent out upon the flanks of an army toguard a line of march, or a fort projecting so as to command the side of an assailing body. "They threw out flankers, and endeavored to dislodge their assailants."
verb
Flanker v. t. (past & past part. flankered; pres. part. flankering)
... again there came sudden and stirring interruption. From a point far down the "swale," from behind the low bank of the stream bed, three rifle shots rang out on the crisp morning air. The horse of the leading flanker, away out to the right, reared and plunged violently, the rider seeming vainly to strive to check him. Almost instantly three mounted warriors were seen tearing madly away northeastward out of the gully, their feathers streaming in the wind. Field spurred away to join his ... — A Daughter of the Sioux - A Tale of the Indian frontier • Charles King