membranous

adjective

mem·​bra·​nous ˈmem-brə-nəs 

1

: of, relating to, or resembling membrane

2

: thin, pliable, and often somewhat transparent

membranous leaves

3

: characterized or accompanied by the formation of a usually abnormal membrane or membranous layer

membranous croup

membranously adverb

Examples of membranous in a Sentence

Recent Examples on the Web

Those are tiny, membranous particles, ranging from 10 microns down to 20 nanometers, that exit cells and dwell in the spaces among them. — New Atlas, 4 Jan. 2026

In a battery, the separator is a thin, membranous material that separates the anode from the cathode in a battery. — Liam Rappleye, Freep.com, 4 Nov. 2025

This fruit of the gods, with its bright yellow pulp and membranous black seeds that look like alien eggs, has many monikers. — Cesar Hernandez, San Francisco Chronicle, 7 Sep. 2024

The cicada bobblehead features prominent red eyes set wide apart, short antennae and membranous wings. — Alex Groth, Journal Sentinel, 21 June 2024

The tiny baby octopuses—each about the size of a nickel—emerged from soft, membranous eggs, clutched in their mothers’ protective embrace. — Ashley Balzer Vigil, Scientific American, 3 July 2023

All three musicians came of age in the era of shuffling playlists and collapsing styles, when the boundaries between rock, folk, hip-hop, and electronic became so membranous that the categories began to lose meaning. — Rachel Syme, The New Yorker, 1 Apr. 2023

Word History

First Known Use

1598, in the meaning defined at sense 1

Phrases Containing membranous

• membranous labyrinth

Rhymes for membranous

• pseudomembranous

Medical Definition

membranous

adjective

mem·​bra·​nous ˈmem-brə-nəs 

1

: of, relating to, or resembling membranes

a membranous lining

2

: characterized or accompanied by the formation of a usually abnormal membrane or membranous layer

membranous croup

membranously adverb