That which is alleged by a party in support of his cause; in
   a stricter sense, an allegation of fact in a cause, as distinguished
   from a demurrer; in a still more limited sense, and in modern practice,
   the defendant's answer to the plaintiff's declaration and demand. That
   which the plaintiff alleges in his declaration is answered and repelled
   or justified by the defendant's plea. In chancery practice, a plea is a
   special answer showing or relying upon one or more things as a cause
   why the suit should be either dismissed, delayed, or barred. In
   criminal practice, the plea is the defendant's formal answer to the
   indictment or information presented against him.