Definition of occlusion in US English:



  • 1Medicine
    The blockage or closing of a blood vessel or hollow organ.

    • ‘The occlusion rates are close to 100%, higher than published results for surgical ligation.’
    • ‘Localized observation of blood vessel stasis, occlusion or vessel dilation have all been observed with Photofrin treatment in vivo.’
    • ‘Two of the 4 patients with cirrhosis had hepatic infusion chemotherapy and therapeutic occlusion of hepatic arteries.’
    • ‘The blood vessel wall is usually involved early with resultant hemorrhage, thrombotic occlusion, and lung infarction.’
    • ‘Cardiac catheterization can confirm vascular occlusion and angioplasty is frequently used to treat a localized problem.’
    obstruction, stoppage, block, clot
    blockage, obstruction, obstructing, blocking, blocking up, closing, closing up, closure
    View synonyms
    1. 1.1Phonetics The momentary closure of the passage of breath during the articulation of a consonant.
  • 2Meteorology
    A process in which the cold front of a rotating low-pressure system overtakes the warm front, forcing the warm air upward above a wedge of cold air.

    • ‘In a cold occlusion, the reverse occurs and the occlusion resembles a cold front.’
    • ‘The second type is a warm occlusion, which occurs when the air behind the front is warmer than the air ahead of the front.’
    1. 2.1 An occluded front.
      • ‘The meteorological language, which Doogan edits slightly, destabilizes into a poetry of cyclones, occlusions and disturbances.’
      • ‘In both types of occlusions, the occluded front has well defined vertical boundaries between the coldest air, the cool air, and the warm air.’
  • 3Dentistry
    The position of the teeth when the jaws are closed.

    • ‘The initial jaw position was obtained with the teeth in centric occlusion.’
    • ‘Posterior teeth may need to be replaced to restore occlusion.’
    • ‘The multi-cusped cheek teeth, complex occlusion and extensive palinal power stroke were well suited for shredding fibrous plant material.’
    • ‘The lowered position of these surfaces require downward flexion of the rostrum in order to maintain occlusion of upper and lower incisors.’


Mid 17th century: from Latin occlus- ‘shut up’ (from the verb occludere) + -ion.