hydro
noun
hydroelectric power.
hydro
1 American
[hahy-droh]
/ ˈhaɪ droʊ /
noun
-
hydros
plural
-
Informal. hydroelectric power.
-
Informal. hydroplane.
-
British.
-
a bathhouse, hotel, or resort catering to people taking mineral-water health cures; spa.
-
an establishment furnishing hydrotherapy.
-
adjective
hydro-
2
American
hydro-
3
American
hydro
1
British
/ ˈhaɪdrəʊ /
adjective
noun
Hydro
2
British
/ ˈhaɪdrəʊ /
noun
hydro
3
British
/ ˈhaɪdrəʊ /
noun
hydro-
4
British
combining form
-
indicating or denoting water, liquid, or fluid
hydrolysis
hydrodynamics
-
indicating the presence of hydrogen in a chemical compound
hydrochloric acid
-
indicating a hydroid
hydrozoan
hydro–
Scientific
Usage
What does hydro- mean? Hydro- is a combining form used like a prefix that has two distinct senses. The first of these senses is “water,” and this form of hydro- is often used in a variety of scientific and technical terms. Hydro- comes from Greek hýdōr, meaning “water.”The second of these senses is “hydrogen,” and this form of hydro- is occasionally used in a variety of scientific terms, especially in chemistry. Hydrogen, the lightest of the elements, combines with oxygen to form water. The word hydrogen comes from French hydrogène. The suffix -gen, or its equivalent in French, means "that which produces." Hydrogen literally translates to "that which produces water."What are variants of hydro-?When combined with words or word elements that begin with a vowel, hydro- becomes hydr-, as in hydrant. Want to know more? Read our Words That Use article on hydr-.
Other Word Forms
Noun Inflected Forms
Etymology
Origin of hydro1
1880–85; by shortening of compounds with hydro- 1 ( cf. -o); hydro ( def. 4 ) hydro- 1 analyzed as an adj.
Origin of hydro-2
< Greek, combining form of hýdōr water
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Massachusetts requires roughly 69% of electricity supply to come from qualifying renewable or clean-energy sources like Canadian hydro.
From MarketWatch ● Sep. 10, 2026
“In Genesis’s favor is the short-term South Island hydro position,” he says.
From The Wall Street Journal ● Aug. 28, 2026
He thought solar, wind and hydro power would each present their own environmental problems.
From Salon ● Jun. 26, 2026
“I will advance renewable energy, import less foreign fuel and stop decommissioning of hydro and nuclear power. However, many current initiatives have unintended consequences, and my plan focuses on incentives, not mandates,” she said.
From Los Angeles Times ● May 1, 2026
The editor was still not hack from covering a plowing match; his mother said that the hydro maintenance crew covered a large area of the country...
From "The Incredible Journey" by Sheila Burnford
By choosing certain spots, each species is hydro- and thermoregulating, Muñoz says.
From Science Magazine ● Sep. 22, 2022
The energy business would encompass equipment and services for gas, coal and wind turbines, hydro-, nuclear and electric power generation.
From Reuters ● Nov. 10, 2021
Solar projects accounted for 60 percent of the projects, while hydro- electric plants were 75 percent of new capacity.
From BusinessWeek ● Sep. 8, 2011
Other Series.—In addition to the two series of hydro- carbons above given, CnH2n+2 and CnH2n, other series are known with the general formulm CnH2n-2, CnH2n-4, CnH2n-6, CnH2n-8, etc., as far as CnH2n-32, or C26H2O.
From An Introduction to Chemical Science by Rufus Phillips Williams
But enough of these follies: ‘Necro-, pyro-, geo-, hydro-, cheiro-, coscinomancy, With other vain and superstitious sciences.’
From Witch, Warlock, and Magician Historical Sketches of Magic and Witchcraft in England and Scotland by W. H. Davenport (William Henry Davenport) Adams
During the war, the only European facility capable of supplying the heavy water needed by the German program was the Norsk Hydro plant in Vemork, Norway.
From Science Daily ● Oct. 16, 2026
Norsk Hydro NHY -0.91%decrease; red down pointing triangle said it expects a further financial hit in the fourth quarter following gas supply challenges at its alumina refinery in Brazil.
From The Wall Street Journal ● Oct. 6, 2026
Find insight on gold futures, Talon Metals, Norsk Hydro and more in the latest Market Talks covering Basic Materials.
From The Wall Street Journal ● Sep. 14, 2026
At the Chilime Hydro tunnel, where Indian teams are deployed, rescuers entered 100 metres inside, but then said it was blocked.
From Barron's ● Aug. 31, 2026
He bought a ticket and traveled down the lake on Hydro, leaning over the rail, with one eye on the minute hand of his watch.
From "Bomb" by Steve Sheinkin
It was a rough weekend for the hydros.
From Seattle Times ● Jul. 31, 2022
For that, you gotta wait for the hydros, another tradition we’ll have to explain.
From Seattle Times ● May 6, 2016
So many of us grew up with hydros; tons of us still follow them to this day.
From Seattle Times ● Jul. 10, 2011
A fleet of 180-mph hydros throw long roostertails over three days.
From Time Magazine Archive
She knew dozens of hydros, and warned me how to behave in them, while Mr. and Mrs. M'Leod stood aside and adored her.
From Actions and Reactions by Rudyard Kipling
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