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definitions

rehydrate

[ree-hahy-dreyt]

verb (used with object), re·hy·drat·ed, re·hy·drat·ing.

to restore moisture or fluid to (something dehydrated).

Origin of rehydrate

1920–25; re- + hydrate, on the model of dehydrate
Related formsre·hy·dra·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for rehydrate
v.

1923, from re- + hydrate (v.). Related: Rehydrated; rehydrating.

Online Etymology Dictionary, © 2010 Douglas Harper
rehydrate in Medicine

rehydrate

[rē-hī′drāt′]

v.

To cause rehydration of something.
To replenish the body fluids of an individual.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.