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/ˌäkyəlōˈmōtər/ Adjective 1. Moving or tending to move the eyeball. ( 2. Of or relating to the oculomotor nerve. ( 3. Of or pertaining to the movement of the eye; applied especially to the common motor nerves (or third pair of cranial nerves) which supply many of the muscles of the orbit. ( Noun 1. An oculomotor part; especially oculomotor nerve....

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Oculomotor nerve

pl. oculomotor nerves 1. The 3rd of 12 paired cranial nerves. It enters the orbit via the superior orbital fissure and controls most of the eye’s movements, including constriction of the pupil and maintaining an open eyelid by innervating the levator palpebrae superioris muscle. The oculomotor nerve is derived from the basal plate of the embryonic midbrain. Cranial nerves IV and VI also participate in control of eye movement. ( 2. Either nerve of the third pair of cranial nerves that are motor nerves with some associated autonomic fibers, arise from the midbrain, supply muscles of the eye except the superior oblique and the lateral rectus with motor fibers, and supply the ciliary body and iris with autonomic fibers by way of the ciliary ganglion. ( 3. The occulomotor nerve is responsible for motor enervation of upper eyelid muscle, extraocular muscle and pupillary muscle. Lesions of the oculomotor nerve results in ptosis (dropping eyelid), deviation of the eyeball outward, double vision and a dilated pupil. ( Syn: nervus oculomotorius, third cranial...

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/ˈäkyələs/ Noun, pl. oculi 1. (Botany) An eye; a leaf bud. ( 2. A window or other opening that has an oval or circular shape (as of an eye). ( 3. The organ of sight. ( 4. The central boss of a volute. (Google Dictionary) 5. An opening at the apex of a dome. (Google Dictionary) Word origin: From Latin oculus...

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/ōˈdäntoid/  Adjective 1. Having the form of a tooth. ( 2. Of or relating to the dens. ( 3. Resembling a tooth, especially in shape. ( 4. A toothlike projection from the second cervical vertebra on which the first vertebra pivots. (Google...

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Odontoid process

1. A protuberance (process or projection) of the axis (second cervical vertebra). It exhibits a slight constriction or neck, where it joins the main body of the vertebra. The condition, where the dens is separated from the body of the axis, is called os odontoideum, and may cause nerve and circulation compression syndrome. ( 2. A toothlike process at the back of 2nd vertebra of the neck. ( 3. A small, toothlike, upward projection from the second vertebra of the neck around which the first vertebra rotates. (The American Heritage® Dictionary of the English Language) 4. The toothlike process on the upper surface of the axis, which articulates with the atlas above. ( Syn: Dens, odontoid...

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