Definition of COUNTERBORE. : to form a counterbore in: enlarge (part of a hole) by means of a counterbore.ADVERTISEMENT.efinition of COUNTERBORE. 1. : a flat-bottomed enlargement of the mouth of a cylindrical bore. 2. : a drill for making a counterbore â compare countersink.
The vestibulocochlear nerve (auditory vestibular nerve) , known as the eighth cranial nerve, transmits sound and equilibrium (balance) information from the inner ear to the brain.
Four of the cranial nerves supply parasympathetic innervation to the majority of the body's glands and internal organs; the oculomotor nerve (III), facial nerve (VII), glossopharyngeal nerve (IX) and the vagus nerve (X).our of the cranial nerves supply parasympathetic innervation to the majority of the body's glands and internal organs; the oculomotor nerve (III), facial nerve (VII), glossopharyngeal nerve (IX) and the vagus nerve (X).