Pledge, v. t. [imp. & p. p.Pledged (?); p. pr. & vb. n.Pledging.] [Cf. OF. pleiger to give security. See Pledge, n.] 1. To deposit, as a chattel, in pledge or pawn; to leave in possession of another as security; as, to pledge one's watch.
2. To give or pass as a security; to guarantee; to engage; to plight; as, to pledge one's word and honor.
We mutually pledge to each other our lives, our fortunes, and our sacred honor. The Declaration of Independence.
3. To secure performance of, as by a pledge.
To pledge my vow, I give my hand. Shak.
4. To bind or engage by promise or declaration; to engage solemnly; as, to pledge one's self.
5. To invite another to drink, by drinking of the cup first, and then handing it to him, as a pledge of good will; hence, to drink the health of; to toast.
Pledge me, my friend, and drink till thou be'st wise. Cowley.