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

Then, there’s damage from heat styling, chemicals, harsh shampoos, or rough handling makes the cuticle more porous, allowing excess moisture in and increasing frizz. —Anna Cafolla, Vogue, 26 Nov. 2025

But for all the good things that happened, the Clippers couldn’t shake the losses, the injuries, fix their porous defense (especially in transition), or their lack of cohesion on offense, troubling signs that are becoming more apparent to opponents. —Janis Carr, Oc Register, 24 Nov. 2025

Essentially desert country, its porous, sandy soil is inhospitable to all but a few types of shallow-root crops. —Sean Patrick Cooper, Rolling Stone, 24 Nov. 2025

The boundaries of their politics, personal lives, and morality are porous. —Angelica Jade Bastién, Vulture, 24 Nov. 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