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definitions

obstruct

[uhb-struhkt]
verb (used with object)
  1. to block or close up with an obstacle; make difficult to pass: Debris obstructed the road.
  2. to interrupt, hinder, or oppose the passage, progress, course, etc., of.
  3. to block from sight; to be in the way of (a view, passage, etc.).

Origin of obstruct

First recorded in 1605–15, obstruct is from the Latin word obstructus (past participle of obstruere to build or pile up in the way, bar). See ob-, construct
Related formsob·struct·ed·ly, adverbob·struct·er, ob·struc·tor, nounob·struct·ing·ly, adverbob·struc·tive, adjectiveob·struc·tive·ly, adverbob·struc·tive·ness, ob·struc·tiv·i·ty [ob-struhk-tiv-i-tee] /ˌɒb strʌkˈtɪv ɪ ti/, nounnon·ob·struc·tive, adjectivenon·ob·struc·tive·ly, adverbnon·ob·struc·tive·ness, nounpre·ob·struct, verb (used with object)un·ob·struct·ed, adjectiveun·ob·struc·tive, adjective

Synonyms for obstruct

1. stop, choke, clog, hinder, impede, prevent; check, slow, retard, arrest.

Antonyms for obstruct

1. encourage, further.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for unobstructive

obstruct

verb (tr)
  1. to block (a road, passageway, etc) with an obstacle
  2. to make (progress or activity) difficult
  3. to impede or block a clear view of
Derived Formsobstructor, nounobstructive, adjective, nounobstructively, adverbobstructiveness, noun

Word Origin for obstruct

C17: Latin obstructus built against, past participle of obstruere, from ob- against + struere to build
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 unobstructive

obstruct

v.

1610s, a back-formation from obstruction or else from Latin obstructus, past participle of obstruere "to block, to stop up" (see obstruction). Related: Obstructed; obstructing.

Online Etymology Dictionary, © 2010 Douglas Harper
unobstructive in Medicine

obstruct

[əb-strŭkt′, ŏb-]
v.
  1. To block or close a body passage so as to hinder or interrupt a flow.
Related formsob•struc′tive adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.