Permeant

Part of speech: adjective

Definitions

1. Having the ability to spread or pass through a substance or medium freely
2. Characterizing something that can infiltrate or penetrate various materials or environments
3. Describing an entity that allows for the movement or diffusion of particles across boundaries or barriers

Etymology: The "permeant" in "permeant membrane" is a plain English build: take "permeate" and add the suffix "-ant," which forms adjectives meaning "having the quality of doing the action." Permeate itself comes from the Latin "permeare," meaning "to pass through," built from "per" ("through") and "meare" ("to go"). The suffix traces back through Latin "-ans" and "-ānsa" and Old French "-ant" to a Proto-Indo-European participle ending, so the adjective inherits a very old way of turning a verb into a describing word. Because the word is formed directly in English from an existing verb, there is no separate foreign history for it to carry. Its meaning follows the verb closely: a permeant substance is one that can pass through a barrier, such as a gas through a membrane or a drug through skin.

Synonyms: permeable, penetrable, open, porous, accessible

Antonyms: impermeable, sealed, nonpermeable, closed, tight