1. Physiology. of or relating to hypertonia.
  2. Physical Chemistry. noting a solution of higher osmotic pressure than another solution with which it is compared (opposed to hypotonic).Compare isotonic(def 1).

Origin of hypertonic

First recorded in 1850–55; hyperton(ia) + -ic
Related formshy·per·to·nic·i·ty [hahy-per-toh-nis-i-tee] /ˌhaɪ pər toʊˈnɪs ɪ ti/, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for hypertonic

Historical Examples of hypertonic

  • We have seen that a centre of catabolism is a hypertonic focus of diffusion.

  • Those eggs which form membranes begin to develop, but perish if they are not treated with hypertonic sea-water.

    Darwin and Modern Science

    A.C. Seward and Others

  • If such eggs are afterwards treated for a short period with hypertonic sea-water they develop into normal larvae (plutei).

    Darwin and Modern Science

    A.C. Seward and Others

  • Rogers has reduced the mortality of cholera by intravenous injections of hypertonic saline until it is only 15 per cent.

  • Loeb and Wasteneys found that the hypertonic solution does not increase the rate of oxidations in a fertilized egg.

British Dictionary definitions for hypertonic


  1. (esp of muscles) being in a state of abnormally high tension
  2. (of a solution) having a higher osmotic pressure than that of a specified, generally physiological, solutionCompare hypotonic, isotonic
Derived Formshypertonicity (ˌhaɪpətəʊˈnɪsɪtɪ), 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 hypertonic

1855, from hyper- + tonic. Related: Hypertonia; hypertonicity.

Online Etymology Dictionary, © 2010 Douglas Harper

hypertonic in Medicine


  1. Having extreme muscular or arterial tension; spastic.
  2. Having the higher osmotic pressure of two solutions.
Related formshy′per•to•nici•ty (-tə-nĭsĭ-tē, -tō-) n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.