Odontoceti represent cetaceans with teeth that prey on fish, seals and other cetaceans. There are a few Odontoceti that are toothless but do not have baleen plates to classify them as Mysticeti.

They have one blowhole for respiration that separates into two nasal passages divided by a central septum. The skull is asymmetrical with a region of sacs in the front of the head, called a melon, and a telescopic designed snout. The structure of the skull aids in the process of echolocation.