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The relinquishment or refusal to accept of a right.

In practice it is required of every one to take advantage of his rights at a proper time and, neglecting to do so, will be considered as a waiver. If, for example, a defendant who has been misnamed in the writ and declaration, pleads over, he cannot afterwards take advantage of the error by pleading in abatement, for his plea amounts to a waiver.

In seeking for a remedy the party injured may, in some instances, waive a part of his right, and sue for another; for example, when the defendant has committed a trespass on the property of the plaintiff, by taking it away, and afterwards he sells it, the injured party may waive the trespass, and bring an action of assumpsit for the recovery of the money thus received by the defendant. 1 Chit. Pl. 90.

In contracts, if, after knowledge of a supposed fraud, surprise or mistake, a party performs the agreement in part, he will be considered as having waived the objection. 1 Bro. Parl. Cas. 289.

It is a rule of the civil law, consonant with reason, that any one may renounce or waive that which has been established in his favor: Regula est juris antique omnes licentiam habere his quae pro se introducta sunt, renunciare. Code 2, 3, 29. As to what will amount to a waiver of a forfeiture, see 1 Conn. R. 79; 7 Conn. R. 45; 1 Jo Cas. 125; 8 Pick. 292; 2 N. H, Rep. 120 163; 14 Wend. 419; 1 Ham. R. 21. Vide Verdict.