| Noun | 1. | cephalexin - an oral cephalosporin (trade names Keflex and Keflin and Keftab) commonly prescribe for mild to moderately severe infections of the skin or ears or throat or lungs or urinary tractcephalosporin, Mefoxin - one of several broad spectrum antibiotic substances obtained from fungi and related to penicillin (trade names Mefoxin); addition of side chains has produced semisynthetic antibiotics with greater antibacterial activity | |