What does permeable mean?
Permeable is an adjective describing something that allows fluids, gases, light, or other materials to pass through. In scientific and engineering contexts, a permeable membrane or surface allows substances to cross it, while its opposite, impermeable, means that passage is prevented. The word can also be used figuratively to describe people, organizations, or ideas that are open to outside influence and easy to affect. For example, a permeable material might permit water to pass through, while a permeable social network may allow information to spread rapidly. The term is more common in formal writing than in everyday speech, where simpler words such as “leaky” or “open” may be preferred. Its figurative use is especially useful when describing boundaries that are not firm or resistant, such as cultural divisions, communication channels, or personal defenses.
adjectivePermeable means allowing fluids, gases, light, or other substances to pass through. It can also describe a boundary, material, or system that does not prevent such passage.
- Allowing fluids, gases, light, or other substances to pass through
- Open or easily affected by outside influences, ideas, or emotions
"The membrane is permeable to water but impermeable to larger particles."
"The porous stone is permeable to both air and water."
"A permeable culture can spread new ideas quickly through a community."
Permeable describes anything that lets something through, from a raincoat to an idea that spreads easily through a community.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does permeable come from?
The word comes through Latin permeabilis, meaning “able to be passed through” or “penetrable.” It is derived from permeare, “to pass through or penetrate,” and entered English in the late Middle English period. Its English relatives include permeate, permeation, and permeability, all sharing the same Latin root.
Related word forms
How permeable is actually used
The word is formal and technical in scientific and engineering contexts, especially in discussions of membranes, materials, and environmental systems. In broader figurative use, it suggests receptiveness or ease of influence.
Easily confused with permeable
Permeable allows substances to pass through, whereas impermeable prevents passage.
Pervious often emphasizes porosity or the ability to be penetrated, while permeable is the more technical term for allowing passage through a material or boundary.