【egg】an oval or round object laid by a female bird, reptile, fish, or invertebrate, usually containing a developing embryo. The eggs of birds are enclosed in a chalky shell, while those of reptiles are in a leathery membrane 由雌性鳥類、爬行動物、魚類或無脊椎動物產下的橢圓形或圓形物體,通常包含一個發育中的胚胎。鳥類的卵被包在白堊質的殼中,而爬行動物的卵則被包在一層皮膜中