‖prop. n. pl. [ NL., from Gr. 'odoy`s, 'odo`ntos, a tooth + &unr_; a furrow. ] (Paleon.) An extinct order of ostrichlike aquatic birds having teeth, which are set in a groove in the jaw. It includes Hesperornis, and allied genera. See Hesperornis. [ Written also Odontholcae, and Odontoholcae. ] [ 1913 Webster ]