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Archives: Dictionary

Occiput

/ˈäksəpət/ Noun, pl. occipita 1. The anatomical term for the posterior (back) portion of the head or skull. In insects, the occiput is the posterior part of the head capsule. (wikipedia.org) 2. The back part of the head or skull (contradistinct from sinciput). (wiktionary.org) Word origin: From Latin occiput, occipitium “the back part of the head”, from ob “over against” + caput...

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Occlusion

/əˈklo͞oZHən/ Noun, pl. occlusions (Medicine) 1. Anything that obstructs or closes a vessel or canal. (wiktionary.org) 2. The alignment of the teeth when upper and lower jaws are brought together. (wiktionary.org) 3. The relationship between all of the components of the masticatory system in normal function, dysfunction and parafunction. (biology-online.org) 4. Momentary complete closure of some area in the vocal tract, causing stoppage of the breath and accumulation of pressure. (biology-online.org) (Physics) The absorption of a gas or liquid by a substance such as a metal. (wiktionary.org) (Meteorology) 1. An occluded front. (wiktionary.org) 2. The process of occluding air masses. (merriam-webster.com) (Linguistics) 1. A closure within the vocal tract that produces an oral stop or nasal stop. (wiktionary.org) 2. Closure at some point in the vocal tract that blocks the flow of air in the production of an oral or nasal stop. (merriam-webster.com) (Computing) The blocking of the view of part of an image by another. (wiktionary.org) (General definition) 1. The process of occluding, or something that occludes. (wiktionary.org) Word origin: From Medieval Latin occlusionem (nominative occlusio), noun of action from past participle stem of Latin occludere (past participle occlusus) “shut up, close up,” from ob “against, up” + claudere “to shut,...

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Oculomotor

/ˌäkyəlōˈmōtər/ Adjective 1. Moving or tending to move the eyeball. (merriam-webster.com) 2. Of or relating to the oculomotor nerve. (merriam-webster.com) 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. (biology-online.org) 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. (wikipedia.org) 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. (merriam-webster.com) 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. (biology-online.org) Syn: nervus oculomotorius, third cranial...

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Oculus

/ˈäkyələs/ Noun, pl. oculi 1. (Botany) An eye; a leaf bud. (biology-online.org) 2. A window or other opening that has an oval or circular shape (as of an eye). (wiktionary.org) 3. The organ of sight. (wordnetweb.princeton.edu) 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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