A defeasance, or defeazance (Fr. défaire, to undo), in law, is an instrument which defeats the force or operation of some other deed or estate; as distinguished from a condition— that which in the same deed is called a condition is a defeasance in another deed. A defeasance should recite the deed to be defeated and its date, and it must be made between the same parties as are interested in the deed. It must be of a thing defeasible, and all the conditions must be strictly carried out before the defeasance can be consummated.
Defeasance in a bill of sale is the putting of an end to the security by realizing the goods for the benefit of the mortgagee. It is not strictly a defeasance, because the stipulation is in the same deed; it is really a condition in the nature of a defeasance.