An instrument which defeats the force or operation of some otherdeed or estate. That which is in the same deed is called a “condition;” and that which isin another deed is a “defeasance.” Com. Dig. “Defeasance.”In conveyancing. A collateral deed made at the same time with a feoffment or otherconveyance, containing certain conditions, upon the performance of which the estatethen created may be defeated or totally undone. 2 Bl. Comm. 327 ; Co. Litt. 236, 237.An instrument accompanying a bond, recognizance, or judgment, containing a conditionwhich, when performed, defeats or undoes it. 2 Bl. Comm. 342; Co. Litt. 230,237; Miller v. Quick, 158 Mo. 495, 59 S. W. 955; Harrison v. Philips’ Academy, 12 Mass.456; Lippincott v. Tilton, 14 N. J. Law, 361; Nugent v. Itiley, 1 Mete. (Mass.) 119, 35Am. Dec. 355.