1. (v. t.) To unite or join; to link closely together; to bring into harmonious union; to cause or unite so as to form a homogeneous substance, as by chemical union.

2. (v. t.) To bind; to hold by a moral tie.

3. (v. i.) To form a union; to agree; to coalesce; to confederate.

4. (v. i.) To unite by affinity or natural attraction; as, two substances, which will not combine of themselves, may be made to combine by the intervention of a third.

5. (v. i.) In the game of casino, to play a card which will take two or more cards whose aggregate number of pips equals those of the card played.