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

• 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

Bleach also does not deal with roots of mold colonies growing on porous surfaces. —Daley Quinn, Southern Living, 5 July 2025

Social media and hybrid workplaces have made our environments even more porous such that contagion spreads faster—emotionally and professionally. —Ellen Choi, Forbes.com, 30 June 2025

Mold spores can cling to porous surfaces, and even after washing, lingering odors or stains might leave you unsure if the container is truly clean. —Mary Cornetta, Better Homes & Gardens, 30 June 2025

The best versions have carbon filters with porous surfaces that trap the gas molecules of VOCs, taking them out of the air. —Matt Fuchs, Time, 12 June 2025

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