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

Terracotta pots are porous and allow excess moisture to evaporate quickly. —Karen Brewer Grossman, Southern Living, 22 Oct. 2025

This season, these players, this staff — there’s an edge, sponsored by the Gators’ porous start and a hope to turn things around, despite facing three top-17 opponents in the coming weeks. —Noah White, Miami Herald, 21 Oct. 2025

Instead, sloth teeth are made primarily of dentin, a more porous and organic-rich tissue that readily changes its chemical composition with fossilization. —Aditya Reddy Kurre, The Conversation, 21 Oct. 2025

What’s the excuse for the porous defense? —Ryan Finley, San Diego Union-Tribune, 20 Oct. 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