cognovit

from The Collaborative International Dictionary of English v.0.48

Cognovit \Cog*no"vit\, n. [L., he has acknowledged.] (Law)
   An instrument in writing whereby a defendant in an action
   acknowledges a plaintiff's demand to be just. --Mozley & W.
   [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

COGNOVIT, contr. leading. A written confession of an action by a defendant, 
subscribed but not sealed, and authorizing the plaintiff to sign judgment 
and issue execution, usually for a sum named. 
     2. It is given after the action is brought to save expense. 
     3. It differs from a warrant of attorney, which is given before the 
commencement of any action, and is under seal. A cognovit actionem is an 
acknowledgment and confession of the plaintiff's cause of action against the 
defendant to be just and true. Vide 3 Ch. Pr. 664; 3 Bouv. Inst. n. 8299.