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porous

[pawr-uh s, pohr-] /ˈpɔr əs, ˈpoʊr-/
adjective
1.
full of pores.
2.
permeable by water, air, etc.
Origin of porous
1350-1400
1350-1400; Middle English, variant of porose < Medieval Latin porōsus. See pore2, -ous
Related forms
porously, adverb
porousness, noun
nonporous, adjective
nonporousness, noun
unporous, adjective
unporousness, noun
Synonyms
2. penetrable, pervious, sievelike, riddled.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Examples from the Web for porous
Contemporary Examples
Historical Examples
  • The soft layers are porous, and permit the diffusion of the acid from plate to plate.

  • Hanging from one of the sticks that supported the tent was a porous jar of water.

    At Aboukir and Acre George Alfred Henty
  • Papillate -us: a surface with small elevations which are porous at tip.

  • It should be porous in a high degree—whether in winter weight or summer weight.

    Textiles

    William H. Dooley
  • The vein was porous and water was constantly trickling out of it.

    Diggers in the Earth Eva March Tappan
British Dictionary definitions for porous

porous

/ˈpɔːrəs/
adjective
1.
permeable to water, air, or other fluids
2.
(biology, geology) having pores; poriferous
3.
easy to cross or penetrate: the porous border into Thailand, the most porous defence in the league
Derived Forms
porously, adverb
porousness, noun
Word Origin
C14: from Medieval Latin porōsus, from Late Latin poruspore²
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
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Word Origin and History for porous
adj.

late 14c., "full of pores," from Old French poros (14c., Modern French poreux), from Medieval Latin porosus; or directly from Latin porus "an opening" (see pore (n.)). Figurative use from 1640s.

Online Etymology Dictionary, © 2010 Douglas Harper
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porous in Medicine

porous po·rous (pôr'əs)
adj.

  1. Full of or having pores.

  2. Admitting the passage of gas or liquid through pores.


po'rous·ness n.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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porous in Science
porous
  (pôr'əs)   
Having many pores or other small spaces that can hold a gas or liquid or allow it to pass through.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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