trigeminus Definition

either of the fifth pair of cranial nerves that are mixed nerves and in humans are the largest of the cranial nerves and that arise by a small motor root and a larger sensory root which both emerge from the side of the pons with the sensory root bearing the trigeminal ganglion and dividing into ophthalmic, maxillary, and mandibular nerves and the motor root supplying fibers to the mandibular nerve and through this to the muscles of mastication —called also fifth cranial nerve, trifacial nerve, trigeminus