occlusion

UK: /əˈkluːʒən/ US: /əˈkluʒən/ ,(ə klo̅o̅′zhən)

WordReference Random House Unabridged Dictionary of American English © 2026

oc•clu•sion  (ə klo̅o̅′zhən), n. 

1. the act or state of occluding or the state of being occluded.
2. Dentistry the fitting together of the teeth of the lower jaw with the corresponding teeth of the upper jaw when the jaws are closed.
3. Pathology closure or blockage of a blood vessel:
   coronary occlusion.
4. Phonetics momentary complete closure at some area in the vocal tract, causing stoppage of the flow of air and accumulation of pressure.
5. Meteorology
   • the formation of an occluded front.
   • See occluded front. 

• Latin occlūs(us) (past participle of occlūdere to occlude) + -ion
• 1635–45;

oc•clu•sal  (ə klo̅o̅′səl, -zəl), adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

occlusion / əˈkluːʒən/ noun

1. the act or process of occluding or the state of being occluded
2. another term for occluded front
3. the normal position of the teeth when the jaws are closed

WordReference Random House Learner's Dictionary of American English © 2026

oc•clude /əˈklud/   v., -clud•ed, -clud•ing. 

1. to (cause to) be closed, shut, or stopped up, as a passage or opening: [~ + object]
   Something occluded the drainpipe.
   [no object]
   The drainpipe occluded.
2. Dentistry [no object] (of a tooth) to make contact with the surface of an opposite tooth when the jaws are closed.

oc•clu•sion /əˈkluʒən/  n. 

[countable] an occlusion of the teeth.

[uncountable] improper occlusion.

oc•clu•sive /əˈklusɪv/  adj. 

WordReference Random House Unabridged Dictionary of American English © 2026

oc•clude  (ə klo̅o̅d′), v., -clud•ed, -clud•ing. 
v.t. 

1. to close, shut, or stop up (a passage, opening, etc.).
2. to shut in, out, or off.
3. Chemistry [Physical Chem.] (of certain metals and other solids) to incorporate (gases and other foreign substances), as by absorption or adsorption.

v.i. 

4. Dentistry to shut or close, with the cusps of the opposing teeth of the upper and lower jaws fitting together.
5. Meteorology to form an occluded front.

• Latin occlūdere to shut up, close up, equivalent. to oc- oc- + -clūdere, combining form of claudere to close
• 1590–1600

oc•clud′ent, adj. 
Synonyms

• 1. obstruct, clog, block, plug.