hydrate

American  

[hahy-drayt] / ˈhaɪ dreɪt /

noun

• hydrates
  plural

1. any of a class of compounds containing chemically combined water. In the case of some hydrates, as washing soda, Na 2 CO 3 ⋅10H 2 O, the water is loosely held and is easily lost on heating; in others, as sulfuric acid, SO 3 ⋅H 2 O, or H 2 SO 4 , it is strongly held as water of constitution.

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verb (used with or without object)

• hydrates,
  present (3rd person singular)
• hydrated,
  past participle,  past
• hydrating
  present participle

1. to combine chemically with water.

hydrate British  

/ ˈhaɪdreɪt /

noun

1. a chemical compound containing water that is chemically combined with a substance and can usually be expelled without changing the constitution of the substance

2. a chemical compound that can dissociate reversibly into water and another compound. For example sulphuric acid (H 2 SO 4 ) dissociates into sulphur trioxide (SO 3 ) and water (H 2 O)

3. (not in technical usage) a chemical compound, such as a carbohydrate, that contains hydrogen and oxygen atoms in the ratio two to one

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verb

1. to undergo or cause to undergo treatment or impregnation with water

hydrate Scientific  

/ hī′drāt′ /

1. A compound produced by combining a substance chemically with water. Many minerals and crystalline substances are hydrates.

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1. To combine a compound with water, especially to form a hydrate.

2. To supply water to a person in order to restore or maintain a balance of fluids.

Other Word Forms

Derived Forms

• hydration
  noun
• hydrator
  noun

Inflected Forms

Nouns

• hydrates
  plural

Participles

• hydrating
  present
• hydrated
  past

Conjugated Forms

Present

• hydrate
  simple
• hydrates
  simple
• have hydrated
  perfect
• has hydrated
  perfect
• am hydrating
  progressive
• are hydrating
  progressive
• is hydrating
  progressive
• have been hydrating
  perfect progressive
• has been hydrating
  perfect progressive

Past

• hydrated
  simple
• had hydrated
  perfect
• was hydrating
  progressive
• were hydrating
  progressive
• had been hydrating
  perfect progressive

Future

• will hydrate
  simple
• will have hydrated
  perfect
• will be hydrating
  progressive
• will have been hydrating
  perfect progressive

Etymology

Origin of hydrate

First recorded in 1795–1805; hydr- ¹ + -ate ²

Explanation

To hydrate is to add or absorb water. It's hot outside — don't forget to hydrate by drinking plenty of water! If you want to sound fancy, you can use the word hydrate every time you get a drink of water. Along with most organisms, we need to hydrate, or ingest water, to stay alive. This verb is also commonly used to mean "moisturize," as in "this magic cream will hydrate your skin like you won't believe!" As a noun, hydrate refers to a chemical compound that includes water molecules. A French chemist coined the noun in 1800 from the Greek hydor, "water."

Example Sentences

See Examples For:

hydrate hydrates hydrated hydrating

He has to constantly hydrate, so he places big cups of water on both sides of the stage with straws, but sometimes the crew and other actors help him pick up the cup.

From Los Angeles Times ● Aug. 19, 2026

“This is the world’s game ... we have to figure out how to help players at all levels and ages to have the ability to thermoregulate, hydrate, how to do it well.”

From Los Angeles Times ● Jul. 7, 2026

For now, standard European advice remains to close the shutters and windows during the day and to stay indoors and hydrate.

From The Wall Street Journal ● Jun. 26, 2026

Sleep, exercise, hydrate - do we really need to stick to recommended daily doses?

From BBC ● Jun. 20, 2026

Mother called a hospital in Utah and begged them to give her an IV. “I need to hydrate him,” she said.

From "Educated" by Tara Westover

Methanol helps prevent freezing and the accumulation of solid hydrates that can plug gas-compression equipment and limit pipeline flow, and it acts as a solvent and corrosion inhibitor.

From The Wall Street Journal ● Nov. 21, 2025

Water, the main ingredient in most sports drinks, hydrates you.

From Salon ● Jan. 21, 2025

Warming waters and rising temperatures destabilize the hydrates and release the methane into the water column.

From Science Daily ● Nov. 26, 2024

The challenge now is making sure everyone hydrates well to recover as quickly as possible.

From Washington Times ● Dec. 29, 2023

This method of dialysis was applied by Graham to separate and obtain in the pure state many colloidal modifications of chemical compounds, such as aluminium and tin hydrates, etc.

From Heroes of Science Chemists by M. M. Pattison (Matthew Moncrieff Pattison) Muir

Rain watered crops, and soaked in to recharge the groundwater that hydrated the city — something that can’t happen now, when something like 40% of the city is covered over, impermeable to rain.

From Los Angeles Times ● Sep. 17, 2026

Madison and Wall did the same just yesterday, calling out factors including AI; the longer, more-watched and better hydrated World Cup; and consumer spending among the higher-income leg of the K-shaped economy.

From The Wall Street Journal ● Sep. 10, 2026

Like other tour guides, Giusto always urges tourists to stay hydrated, wear a hat and sunscreen.

From BBC ● Aug. 4, 2026

"Move immediately to a cool place, such as a designated cooling centre or a shaded area, and stay hydrated while resting," it advised.

From Barron's ● Aug. 2, 2026

Then he and his wife, whose name is Margaret Ann, wrap them in a refrigerated shipping bucket, which will keep the flowers hydrated.

From "All The Bright Places" by Jennifer Niven

When Tayshia Adams, a TV host and self-professed skincare junkie, double cleanses in the shower, she uses a vitamin C-based exfoliating wash then a hydrating cleanser.

From The Wall Street Journal ● Sep. 11, 2026

After the analysis, she was able to pick from care packages, each with a different purpose, such as slowing aging, hydrating the skin, clarifying it or brightening it.

From Los Angeles Times ● Aug. 17, 2026

The fruit is also made up of about 92% water, making it a hydrating option during hot weather or after exercise.

From Science Daily ● May 17, 2026

That brief chill allows the fat to firm and the panade to finish its quiet work, hydrating and binding.

From Salon ● Mar. 11, 2026

Be sure to moisturize with an ultra- hydrating serum like The Corporation’s new Skin So Right B14 Complex for Total Cell Renewal, made with essential vitamins, minerals, and concentrated yak’s bladder.

From "Beauty Queens" by Libba Bray