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egg tooth
egg toothn. A hard toothlike projection on the beak of an embryonic bird or the snout of an embryonic reptile that is used to break through the eggshell upon hatching and that later falls off or is absorbed.egg tooth n (Zoology) (in embryo birds and reptiles) a temporary tooth or (in birds) projection of the beak used for piercing the eggshell egg′ tooth`
n. a calcareous prominence at the tip of the beak or upper jaw of an embryonic bird or reptile, used to break through the eggshell at hatching. [1890–95] egg tooth A hard, tooth-like projection from the beak of embryonic birds, or from the upper jaw of embryonic reptiles, that is used to cut the egg membrane and shell upon hatching and that later falls off.Egg Tooth
egg tooth[′eg ‚tüth] (vertebrate zoology) A toothlike prominence on the tip of the beak of a bird embryo and the tip of the nose of an oviparous reptile, which is used to break the eggshell. Egg Tooth a hard sharp horny nodule in the embryos of certain reptiles (turtles, crocodiles, tuatara) and birds that develops temporarily on the upper jaw or on the tip of the upper part of the bill, respectively. The egg tooth serves to break through the shell. Immediately after the egg hatches, the egg tooth falls off. In some lizards and snakes the egg tooth is the anterior tooth of the premaxillary bone. egg tooth
egg toothn. A hard toothlike projection on the beak of an embryonic bird or the snout of an embryonic reptile that is used to break through the eggshell upon hatching and that later falls off or is absorbed.egg tooth a small horny projection at the tip of the bill in birds used to pierce the egg shell.ThesaurusSeeegg |