Physiology. (of tissue) having less than the normal tone.
Physical Chemistry. noting a solution of lower osmotic pressure than another solution with which it is compared (opposed to hypertonic).Compare isotonic(def 1).

Origin of hypotonic

First recorded in 1890–95; hypo- + tonic
Related formshy·po·to·nic·i·ty [hahy-poh-toh-nis-i-tee] /ˌhaɪ poʊ toʊˈnɪs ɪ ti/, noun
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Examples from the Web for hypotonic

Historical Examples of hypotonic

  • In a hypotonic solution they swell up and burst, the hmoglobin dissolving in the liquid and colouring it red.

  • Under the influence of such a hypotonic solution the dry cells rapidly swell up, burst, and are dissolved.

  • It gains weight in a hypotonic solution, the water current setting towards the point of higher concentration.

  • A bipolar field has a hypertonic pole or centre of concentration, and a hypotonic pole or centre of dilution.

  • We have thus two poles of diffusion of contrary signs, a hypotonic pole at the water drop, and a hypertonic pole at the salt drop.

British Dictionary definitions for hypotonic



pathol (of muscles) lacking normal tone or tension
(of a solution) having a lower osmotic pressure than that of a specified, generally physiological, solutionCompare hypertonic, isotonic
Derived Formshypotonicity (ˌhaɪpətəˈnɪsɪtɪ), 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 hypotonic

1873, from hypo- + tonic.

Online Etymology Dictionary, © 2010 Douglas Harper

hypotonic in Medicine




Having less than normal tone or tension, as of muscles or arteries.
Having a lower osmotic pressure than a reference solution.
Related formshy′po•to•nici•ty (-tə-nĭsĭ-tē) n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.