porous

American  

[pawr-uhs, pohr-] / ˈpɔr əs, ˈpoʊr- /

adjective

1. full of pores.

2. permeable by water, air, etc.

   Synonyms:

   riddled, sievelike, pervious, penetrable

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porous British  

/ 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

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porous Scientific  

/ pôr′əs /

1. Having many pores or other small spaces that can hold a gas or liquid or allow it to pass through.

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Other Word Forms

• nonporous adjective
• nonporousness noun
• porously adverb
• porousness noun
• unporous adjective
• unporousness noun

Etymology

Origin of porous

First recorded in 1350–1400; Middle English, variant of porose, from Medieval Latin porōsus; pore ², -ous

Example Sentences

Of course, “best” is subjective, given how porous the borders of both “celebrity” and “memoir” have become.

From Los Angeles Times

At the time, they were still intensely focused on preventing terrorists trained in foreign lands from infiltrating America’s porous borders — as the 9/11 hijackers had.

From Los Angeles Times

The heist shocked France and turned a spotlight on the porous security system of the Louvre and other museums across the country that have become the target of an increasing number of robberies.

From The Wall Street Journal

The compilation accords dignity to the field and underscores the porous boundary between commercial and fine art.

From The Wall Street Journal

Lab work revealed that, upon exposure to a flame, one of the gels he was working on bubbled up to form a porous aerogel structure within it that is highly protective against fire.

From BBC