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definitions

semipermeable

[sem-ee-pur-mee-uh-buh l, sem-ahy-]
adjective
  1. permeable only to certain small molecules: a semipermeable membrane.

Origin of semipermeable

First recorded in 1895–1900; semi- + permeable
Related formssem·i·per·me·a·bil·i·ty, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for semi-permeable

Historical Examples of semi-permeable

  • The term "osmotic membrane" should therefore in all cases replace that of "semi-permeable membrane."

British Dictionary definitions for semi-permeable

semipermeable

adjective
  1. (esp of a cell membrane) selectively permeable
Derived Formssemipermeability, noun
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
Word Origin and History for semi-permeable
adj.

1873, from semi- + permeable. Translating German halbdurchlässig.

Online Etymology Dictionary, © 2010 Douglas Harper
semi-permeable in Medicine

semipermeable

[sĕm′ē-pûr′mē-ə-bəl, sĕm′ī-]
adj.
  1. Partially permeable.
  2. Allowing passage of certain, especially small, molecules or ions but acting as a barrier to others. Used of biological and synthetic membranes.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.