tetrapod: Meaning and Definition of

tet•ra•pod

1. any vertebrate having four limbs or, as in the snake and whale, having had four-limbed ancestors.
2. an object, as a caltrop, having four projections radiating from one central node, with each forming an angle of 120° with any other, so that no matter how the object is placed on a relatively flat surface, three of the projections will form a supporting tripod and the fourth will point directly upward.

1. having four limbs or descended from four-limbed ancestors.