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90s Slang You Should Know


[pawr-uh s, pohr-] /ˈpɔr əs, ˈpoʊr-/
full of pores.
permeable by water, air, etc.
Origin of porous
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
2. penetrable, pervious, sievelike, riddled. 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
  • Nitroglycerine, when absorbed in a porous earth called 'Kieselguhr', is called dynamite.

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

    Diggers in the Earth Eva March Tappan
  • I prefer bottom land, clay soil and a porous subsoil, with a north and east slope.

    The Apple Various
  • Since they possess pores or vessels, the hardwoods are called "porous" woods.

    Seasoning of Wood Joseph B. Wagner
  • There, as here, the substratum is porous limestone; and it is the subsidence of the layers which gives birth to the springs.

British Dictionary definitions for porous


permeable to water, air, or other fluids
(biology, geology) having pores; poriferous
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

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)

  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
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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