‖n. pl. [ NL. ] (Zool.) One of the grand divisions of the animal kingdom, comprising all animals that have a backbone composed of bony or cartilaginous vertebrae, together with Amphioxus in which the backbone is represented by a simple undivided notochord. The Vertebrata always have a dorsal, or neural, cavity above the notochord or backbone, and a ventral, or visceral, cavity below it. The subdivisions or classes of Vertebrata are Mammalia, Aves, Reptilia, Amphibia, Pisces, Marsipobranchia, and Leptocardia. [ 1913 Webster ]

n. (Zool.) One of the Vertebrata. [ 1913 Webster ]

{ } a. [ L. vertebratus. ] 1. (Anat.) Having a backbone, or vertebral column, containing the spinal marrow, as man, quadrupeds, birds, amphibia, and fishes. [ 1913 Webster ]

2. (Bot.) Contracted at intervals, so as to resemble the spine in animals. Henslow. [ 1913 Webster ]

3. (Zool.) Having movable joints resembling vertebrae; -- said of the arms of ophiurans. [ 1913 Webster ]

4. (Zool.) Of or pertaining to the Vertebrata; -- used only in the form vertebrate. [ 1913 Webster ]