masticatory muscle morphology trait masseter muscle morphology trait VT:0004235 Any measurable or observable characteristic related to the shape, structure, color, or pattern of the masticatory muscle of the posterior cheek with origin from the inferior border and medial surface of the zygomatic arch, with insertion into the lateral surface of the ramus of the mandible, with nerve supply from the masseteric nerve, and whose action closes the jaw during chewing. Trait.ontology