[ mem-breyn ]
See synonyms for membrane on
  1. Anatomy. a thin, pliable sheet or layer of animal or vegetable tissue, serving to line an organ, connect parts, etc.

  2. Cell Biology. the thin, limiting covering of a cell or cell part.

Origin of membrane

1375–1425; late Middle English; Middle English membraan parchment <Latin membrāna.See member, -an

Other words from membrane

  • mem·brane·less, adjective
  • in·ter·mem·brane, adjective

Words Nearby membrane Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use membrane in a sentence

British Dictionary definitions for membrane


/ (ˈmɛmbreɪn) /

  1. any thin pliable sheet of material

  2. a pliable sheetlike usually fibrous tissue that covers, lines, or connects plant and animal organs or cells

  1. biology a double layer of lipid, containing some proteins, that surrounds biological cells and some of their internal structures

  2. physics a two-dimensional entity postulated as a fundamental constituent of matter in superstring theories of particle physics

  3. a skin of parchment forming part of a roll

Origin of membrane

C16: from Latin membrāna skin covering a part of the body, from membrum member

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for membrane


[ mĕmbrān′ ]

  1. A thin, flexible layer of tissue that covers, lines, separates, or connects cells or parts of an organism. Membranes are usually made of layers of phospholipids containing suspended protein molecules and are permeable to water and fat-soluble substances.

  1. Chemistry A thin sheet of natural or synthetic material that is permeable to substances in solution.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.