Es-tōp'pel, n.

n. [From estop, q. v.] (Law.) A stop; an obstruction or bar to one's alleging or denying a fact contrary to his own previous action, allegation, or denial; a conclusive admission, which can not be denied or controverted. Wharton. Stephen. Burrill.

If a tenant for years levies a fine to another person, it shall work as an estoppel to the cognizor. Blackstone.