a combining form meaning “water,” used in the formation of compound words: hydroplane; hydrogen.
A Long List of Affixes: Suffixes, Prefixes, and Combining FormsSuffixes -able, -ible, -ile: (form adjs) able to, fit to, worthy, capable; apt to; subject to being ~-ed -ac: one affect with -ac, -al, -ane, -ar, -ary, -ch, -ese, -ic, -ical, -id, -ile, -ine, -ish, -ory: like, of, pertaining to; characterized by -aceae: families of plants -aceous, -ous: resemblance to a substance; full of -acy, -age, -ance, -ancy, -asm, -dom, -ence, -ency, -hood, -ism, -ity, -ment, -mony, -ness, -ry, -ship, …
- hydriodic acid,
- hydroa vacciniforme,
Also especially before a vowel, hydr-1.
Origin of hydro-1
< Greek, combining form of hýdōr water
a combining form representing hydrogen in compound words, denoting especially a combination of hydrogen with some negative element or radical: hydrobromic.
Also especially before a vowel, hydr-2.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
sometimes before a vowel hydr-
indicating or denoting water, liquid, or fluidhydrolysis; hydrodynamics
indicating the presence of hydrogen in a chemical compoundhydrochloric acid
indicating a hydroidhydrozoan
Word Origin for hydro-
from Greek hudōr water
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
A prefix that means: water (as in hydroelectric) or hydrogen, (as in hydrochloride).
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.