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noun oc·clu·sion \ə-ˈklü-zhən\

Definition of occlusion

  1. 1 :  the act of occluding :  the state of being occluded: as a :  the complete obstruction of the breath passage in the articulation of a speech sound b :  the bringing of the opposing surfaces of the teeth of the two jaws into contact; also :  the relation between the surfaces when in contact c :  the inclusion or sorption of gas trapped during solidification of a material

  2. 2 :  the front formed by a cold front overtaking a warm front and lifting the warm air above the earth's surface

Did You Know?

Occlusion is a descendant of the Latin verb occludere, meaning "to close up." "Occludere" in turn comes from the prefix ob-, here meaning "in the way," and the verb claudere, meaning "to close or shut." "Occlusion" is one of many English terms derived from "claudere." Some others are "recluse," "seclusion," and "exclude." An occlusion occurs when something has been closed up or blocked off. Almost all heart attacks are the result of the occlusion of a coronary (heart) artery by a blood clot. When a person's upper and lower teeth form a "malocclusion," they close incorrectly or badly. An occlusion, or occluded front, happens when a fast-moving cold front overtakes a slow-moving warm front and slides underneath it, lifting the warm air and blocking its movement.

Origin and Etymology of occlusion

Latin occludere

First Known Use: circa 1645

Other Climate/Meteorology Terms

Medical Dictionary


noun oc·clu·sion \ə-ˈklü-zhən\

Medical Definition of occlusion

  1. 1:  the act of occluding or the state of being occluded :  a shutting off or obstruction of something <a coronary occlusion>; especially :  a blocking of the central passage of one reflex by the passage of another

  2. 2a:  the bringing of the opposing surfaces of the teeth of the two jaws into contact; also :  the relation between the surfaces when in contactb:  the transient approximation of the edges of a natural opening <occlusion of the eyelids>

  3. 3:  sorption; especially :  sorption of gases

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