The masseter is a thick, rectangular muscle located in the jaw area. It plays a crucial role in the process of chewing by elevating the lower jaw, allowing the teeth to grind food. This muscle is one of the strongest in the human body relative to its size and is essential for mastication. The masseter is one of the primary muscles involved in the movement of the jaw, along with the temporalis and pterygoid muscles. It is innervated by the trigeminal nerve, which is responsible for sensation in the face and motor functions such as biting and chewing.