porous

adjective

po·​rous ˈpȯr-əs 

1

a

: possessing or full of pores

b

: containing vessels

hardwood is porous

2

a

: permeable to fluids

b

: permeable to outside influences

3

: capable of being penetrated

porous national boundaries

porously adverb

porousness noun

Synonyms of porous

• penetrable
• permeable

Examples of porous in a Sentence

The country has a porous border.

a cleaner that should not be used on porous surfaces

Recent Examples on the Web

Hydrogels are flexible materials made from networks of porous polymers. —Neetika Walter, Interesting Engineering, 14 Mar. 2026

Forgetting to Soak the Pots Terracotta is an incredibly porous material and can quickly zap moisture from new potting soil. —Alexandra Kelly, Martha Stewart, 12 Mar. 2026

There is no need to use bleach, soap or a produce wash — fruits and vegetables are porous and can absorb those chemicals, the FDA said. —Sandee Lamotte, CNN Money, 11 Mar. 2026

Even so, forwards Julian Alvarez, Alexander Sorloth, Ademola Lookman and Giuliano Simeone will trouble Spurs’ porous defence. —Anantaajith Raghuraman, New York Times, 10 Mar. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing porous

• diffuse-porous
• ring-porous

Rhymes for porous

• chloris
• chorus
• horus
• lores
• morrice
• morus
• orris
• porus
• torus
• authorise
• clitoris
• liquorice

Kids Definition

porous

adjective

po·​rous ˈpōr-əs 

ˈpȯr-

1

: full of pores

2

: capable of absorbing liquids

Medical Definition

porous

adjective

po·​rous ˈpōr-əs, ˈpȯr- 

1

: possessing or full of pores

porous bones

2

: permeable to fluids