What is the defining characteristic regarding the teeth of a porpoise?

Answer

Spade-shaped

The single most defining characteristic separating a porpoise from a dolphin is that porpoises possess spade-shaped teeth, which are often described as flattened or spatula-like, whereas dolphins typically have conical, pointed teeth.

What is the defining characteristic regarding the teeth of a porpoise?
animalmammalcharacteristiccetaceanporpoise