a. [ Gr. "ra`chis, -ios, the spine + &unr_;&unr_;&unr_;, &unr_;&unr_;&unr_;, a tooth.] (Zool.) Having gular teeth formed by a peculiar modification of the inferior spines of some of the vertebrae, as certain South African snakes (Dasypeltis) which swallow birds' eggs and use these gular teeth to crush them. [1913 Webster]