‖n. pl. [ NL. ] (Zool.) A division of swimming birds which includes the grebes, divers, auks, etc., in which the legs are placed far back. [ 1913 Webster ]
2. (Zool.) Any species of serpentiform lizards of the family Pygopodidæ, which have rudimentary hind legs near the anal cleft, but lack fore legs. [ 1913 Webster ]