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

While federal law already prohibits the unauthorized entry of migrants into the U.S., proponents of the measure say it's needed because the federal government's efforts to stop people from crossing illegally over Arizona's vast, porous border with Mexico have fallen short. —CBS News, 4 June 2024

Regional district attorneys are refusing to prosecute laws already on the books, mayors and police chiefs are tying the hands of officers through policies and intimidation, and the federal government is even suing the state of Texas to ensure the border stays porous. —Jacob Tackett, Baltimore Sun, 15 May 2024

News from the outside world already seeps into the North across its porous border with China. —Sue Mi Terry, Foreign Affairs, 24 Aug. 2021

The master plan incorporated a 10-acre green roof—the heart of a system of wetland gardens, porous paving, hedgerows and bioswales. —William McDonough, Scientific American, 1 July 2017

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