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

The roughness of the steel wool will scratch the tile and not only will you be left with unsightly marks that more than likely cannot be removed, the tile will now be porous. —Maria Sabella, Better Homes & Gardens, 19 June 2025

West Ham were porous defensively before Potter’s arrival in January. —Roshane Thomas, New York Times, 18 June 2025

Meanwhile bronze dies, which are more traditional, produce a textured, porous exterior that better absorbs sauce. —Alana Al-Hatlani, Southern Living, 14 June 2025

There’s no need to use bleach, soap or a produce wash — fruits and vegetables are porous and can absorb the chemicals. —Sandee Lamotte, CNN Money, 11 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