1574, from M.Fr. perfusion, from L. perfusionem (nom. perfusio) "a pouring over," from perfusus, pp. of perfundere "pour out," from per- "throughout" + fundere "pour" (see found (2)).
Main Entry: per·fu·sion Pronunciation: -'fyü-zh&n Function: noun : an act or instance of perfusing; specifically: thepumping of a fluid through an organ or tissue perfusion —Year Book of Urology>