Transfusion \Trans*fu"sion\, n. [L. transfusio: cf. F. transfusion.]

1. The act of transfusing, or pouring, as liquor, out of one vessel into another. --Howell.

2. (Med.) The act or operation of transferring the blood of one man or animal into the vascular system of another; also, the introduction of any fluid into the blood vessels, or into a cavity of the body from which it can readily be adsorbed into the vessels; intrafusion; as, the peritoneal transfusion of milk.

Source: Webster's Revised Unabridged Dictionary (1913)