oc·​clu·​sion | \ ə-ˈklü-zhən How to pronounce occlusion (audio) \

Definition of occlusion

1 : the act of occluding : the state of being occluded: such 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 : the front formed by a cold front overtaking a warm front and lifting the warm air above the earth's surface

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What Do the Words occlusion, recluse, seclusion, and exclude Have in Common?

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.

Examples of occlusion in a Sentence

Recent Examples on the Web

Likewise, compressed sensing could be useful in combating occlusion in facial recognition systems — wearing sunglasses, for example, could be problematic if the eyes are a key variable in the analysis. Jennifer Ouellette, Quanta Magazine, "The Mathematical Shape of Things to Come," 4 Oct. 2013 Tubal Occlusion Also known as a tubal blockage, tubal occlusion is when an ovulated egg is unable to be fertilized by sperm or to reach the endometrial cavity or uterus. Jennifer Gerson, Marie Claire, "Why Can't I Get Pregnant?," 1 Oct. 2018 What's more, Project Stream's source servers appear to render the game at near-max PC settings, especially in crucial categories like ambient occlusion and shadow-map resolution. Sam Machkovech, Ars Technica, "Google’s Project Stream: That’s really a full Assassin’s Creed in my browser," 9 Oct. 2018 That paradox gets to the nub of this administration’s fraught relationship with ventilation and occlusion. Katy Waldman, Slate Magazine, "What “transparency” means to the Trump administration.," 24 July 2017 The occlusion was at first subtle and indeed novel, the sort of anomaly that breathes new life into an old warhorse. Andrew Kahn, Slate Magazine, "A review of the solar eclipse of 2017.," 21 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'occlusion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of occlusion

circa 1645, in the meaning defined at sense 1

History and Etymology for occlusion

Latin occludere

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Statistics for occlusion

Last Updated

22 Jun 2019

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Time Traveler for occlusion

The first known use of occlusion was circa 1645

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More Definitions for occlusion


oc·​clu·​sion | \ ə-ˈklü-zhən How to pronounce occlusion (audio) \

Medical Definition of occlusion

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
2a : the bringing of the opposing surfaces of the teeth of the two jaws into contact also : the relation between the surfaces when in contact
b : the transient approximation of the edges of a natural opening occlusion of the eyelids
3 : sorption especially : sorption of gases

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More from Merriam-Webster on occlusion

Rhyming Dictionary: Words that rhyme with occlusion

Nglish: Translation of occlusion for Spanish Speakers

Britannica English: Translation of occlusion for Arabic Speakers

Comments on occlusion

What made you want to look up occlusion? Please tell us where you read or heard it (including the quote, if possible).


a period when something is suspended

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