Definition
The genus *Physeter* consists of sperm whales, which are famous for their enormous heads and deep-diving capabilities. *Physeter* whales are toothed whales, meaning they have teeth to catch prey. They are one of the largest toothed predators, primarily feeding on squid. This genus belongs to the family Physeteridae. Think of *Physeter* as the 'last name' that all sperm whales share, setting them apart in the family tree. Like the 'Smith' family, but for giant whales.