What is the term for the bony crest on the skull of male gorillas?

The bony crest on the skull of male gorillas is called a sagittal crest. It is a ridge running lengthwise along the skull’s midline, where the sagittal suture lies.

The crest provides extra attachment area for the temporalis muscles, which help close the jaw. In gorillas, especially adult males, powerful chewing muscles and large jaws are associated with a prominent sagittal crest. The feature is therefore not a horn or a separate skull bone, but an adaptation involving the shape of the skull and muscle attachment.

Sagittal crests also occur in other mammals and reptiles, including some carnivores, tapirs, orangutans, and robust fossil hominins such as Paranthropus. A nuchal ridge is located toward the back of the skull, while an occipital torus is a different thickened area on the occipital bone. “Frontal bossing” describes a bulging forehead rather than the characteristic gorilla crest.