any of an order (Mysticeta) of whales with toothless jaws, baleen in the mouth, and a symmetrical skull, consisting of the gray whale, the right whales, and rorquals
See baleen whale in American Heritage Dictionary 4
noun
Any of several usually large whales of the suborder Mysticeti, such as the right whale and rorquals, having a symmetrical skull, two blowholes, and whalebone plates instead of teeth. Also called mysticete, whalebone whale.