[ toh-nis-i-tee ]
/ toʊˈnɪs ɪ ti /


tonic quality or condition.
the state of bodily tone.
Physiology. the normal elastic tension of living muscles, arteries, etc., by which the tone of the system is maintained.


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Origin of tonicity

First recorded in 1815–25; tonic + -ity Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for tonicity

British Dictionary definitions for tonicity

/ (təʊˈnɪsɪtɪ) /


the state, condition, or quality of being tonic
physiol another name for tonus
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

Medical definitions for tonicity

[ tō-nĭsĭ-tē ]


Normal firmness or functional readiness in body tissues or organs.
The sustained partial contraction of resting or relaxed muscles.
The osmotic pressure or tension of a solution, usually relative to that of blood.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.