verb (used with object), oc·clud·ed, oc·clud·ing.
  1. to close, shut, or stop up (a passage, opening, etc.).
  2. to shut in, out, or off.
  3. Physical Chemistry. (of certain metals and other solids) to incorporate (gases and other foreign substances), as by absorption or adsorption.
verb (used without object), oc·clud·ed, oc·clud·ing.
  1. Dentistry. to shut or close, with the cusps of the opposing teeth of the upper and lower jaws fitting together.
  2. Meteorology. to form an occluded front.

Origin of occlude

1590–1600; < Latin occlūdere to shut up, close up, equivalent to oc- oc- + -clūdere, combining form of claudere to close
Related formsoc·clud·ent, adjectiveun·oc·clud·ed, adjective

Synonyms for occlude

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for unoccluded


  1. (tr) to block or stop up (a passage or opening); obstruct
  2. (tr) to prevent the passage of
  3. (tr) chem (of a solid) to incorporate (a substance) by absorption or adsorption
  4. meteorol to form or cause to form an occluded front
  5. dentistry to produce or cause to produce occlusion, as in chewing
Derived Formsoccludent, adjective

Word Origin for occlude

C16: from Latin occlūdere, from ob- (intensive) + claudere to close
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for unoccluded



1590s, from Latin occludere (past participle occlusus) "shut up, close up," from ob "against, up" (see ob-) + claudere "to shut, close" (see close (v.)). Of teeth, 1888 (also cf. occlusion). Related: Occluded; occluding.

Online Etymology Dictionary, © 2010 Douglas Harper

unoccluded in Medicine


  1. To cause to become closed; obstruct.
  2. To prevent the passage of.
  3. To bring together the upper and lower teeth in proper alignment for chewing.
  4. To enclose a virus, as in an inclusion body.
  5. In chemistry, to absorb and retain gases and other substances.
Related formsoc•cludent adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

unoccluded in Science


  1. To force air upward from the Earth's surface, as when a cold front overtakes and undercuts a warm front.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.