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

• passable
• penetrable
• permeable
• pervious

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

But, wicker furniture is especially prone to moisture damage due to its porous wood and synthetic fibers. —Claire Hoppe Norgaard, Better Homes & Gardens, 14 Jan. 2025

That barrier seems especially porous at the moment, and naturally some hand-wringing has followed. —Kaitlyn Tiffany, The Atlantic, 13 Jan. 2025

Another problem: The Chicago common brick found on the sides of the houses is highly porous. —Jeffrey Steele, Forbes, 13 Jan. 2025

For Lahiri, the line between home and library is porous. —Jennifer Wilson, The New Yorker, 13 Jan. 2025

Word History

First Known Use

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

Phrases Containing porous

• diffuse-porous
• ring-porous

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