Occlusion is either the act of blocking something or a specific blockage. There can be occlusions blocking the street or your arteries. When dentists say occlusion, they’re talking about what your teeth look like when your mouth is closed.

An occlusion blocks anything that flows, like cars, people, water, or blood. You can say there's occlusion if a pipe is clogged. If you find out a golf ball was in the pipe, the ball was an occlusion. This word applies to things that block and the act of blocking. People have heart attacks when there's occlusion in their arteries. An overturned truck would be an occlusion on the highway. Occlusions are in the way.

Definitions of occlusion
  1. noun
    the act of blocking
    synonyms: blockage, closure
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    the initial occluded phase of a stop consonant
    type of:
    the act of obstructing
  2. noun
    closure or blockage (as of a blood vessel)
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    a closure of the larynx that blocks the passage of air to the lungs
    occlusion of a blood vessel by an embolus (a loose clot or air bubble or other particle)
    occlusion of a blood vessel by an embolus that has broken away from a thrombus
    the formation or presence of a thrombus (a clot of coagulated blood attached at the site of its formation) in a blood vessel
    coronary occlusion
    occlusion of a coronary artery caused either by progressive atherosclerosis or by a blood clot
    aeroembolism, air embolism, gas embolism
    obstruction of the circulatory system caused by an air bubble as, e.g., accidentally during surgery or hypodermic injection or as a complication from scuba diving
    fat embolism
    serious condition in which fat blocks an artery; fat can enter the blood stream after a long bone is fractured or if adipose tissue is injured or as a result of a fatty liver
    pulmonary embolism
    blockage of the pulmonary artery by foreign matter or by a blood clot
    cerebral thrombosis
    a blood clot in a cerebral artery or vein
    coronary, coronary thrombosis
    obstruction of blood flow in a coronary artery by a blood clot (thrombus)
    milk leg, phlegmasia alba dolens, white leg
    painful thrombosis of the femoral vein in the leg following childbirth
    phlebothrombosis, venous thrombosis
    thrombosis of a vein without prior inflammation of the vein; associated with sluggish blood flow (as in prolonged bedrest or pregnancy or surgery) or with rapid coagulation of the blood
    type of:
    a sudden occurrence of an uncontrollable condition
  3. noun
    an obstruction in a pipe or tube
    synonyms: block, blockage, closure, stop, stoppage
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    breech closer, breechblock
    a metal block in breech-loading firearms that is withdrawn to insert a cartridge and replaced to close the breech before firing
    plug, stopper, stopple
    blockage consisting of an object designed to fill a hole tightly
    vapor lock, vapour lock
    a stoppage in a pipeline caused by gas bubbles (especially a stoppage that develops in hot weather in an internal-combustion engine when fuel in the gas line boils and forms bubbles that block the flow of gasoline to the carburetor)
    bung, spile
    a plug used to close a hole in a barrel or flask
    bottle cork, cork
    the plug in the mouth of a bottle (especially a wine bottle)
    a removable plug for holding water in a tub or basin
    a plug of cotton, wax, or rubber that is fitted into the ear canal for protection against the entry of water or loud noise
    a wooden plug forming a flue pipe (as the mouthpiece of a recorder)
    tampion, tompion
    plug for the muzzle of a gun to keep out dust and moisture
    plug of cotton or other absorbent material; inserted into wound or body cavity to absorb exuded fluids (especially blood)
    spigot, tap
    a plug for a bunghole in a cask
    type of:
    impediment, impedimenta, obstructer, obstruction, obstructor
    any structure that makes progress difficult
  4. noun
    (dentistry) the normal spatial relation of the teeth when the jaws are closed
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    position, spatial relation
    the spatial property of a place where or way in which something is situated
  5. noun
    (meteorology) a composite front when colder air surrounds a mass of warm air and forces it aloft
    synonyms: occluded front
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    (meteorology) the atmospheric phenomenon created at the boundary between two different air masses
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