Its fibers pass downward and forward, to be inserted into the upper half of the ramus as high as the coronoid process of the mandible.

The masseter muscle can become enlarged in patients who habitually clench or grind (with bruxism) their teeth and even in those who constantly chew gum.

This extraoral enlargement may be confused with parotid salivary gland disease, dental infections, and maxillofacial neoplasms.

Singers often experience various kinds of masseter tension, which is often treated with transdermal massages or stretches as a vocal warm-up.

[9][10] The masseter muscle's positioning is a distinguishing feature of hystricognathous creatures such as mole-rats, where it passes partially through the infraorbital foramen and connects to the bone on the opposite side.

In toothed whales, the masseter muscle, made redundant due to a shift in ingesting food from chewing to swallowing, provides the tissue for acoustic fat bodies, including the melon, used for echolocation.