hydrate

1 of 3

noun (1)

hy·​drate ˈhī-ˌdrāt How to pronounce hydrate (audio)
Synonyms of hydrate
: a compound formed by the union of water with some other substance

hydrate

2 of 3

verb

hydrated; hydrating

transitive verb

1
: to cause to take up or combine with water or the elements of water
2
: to supply with ample fluid or moisture
hydrates and softens the skin

intransitive verb

: to become a hydrate
hydration
hī-ˈdrā-shən How to pronounce hydrate (audio)
noun
hydrator
ˈhī-ˌdrā-tər How to pronounce hydrate (audio)
noun

hydrator

3 of 3

noun (2)

hy·​dra·​tor ˈhīˌdrātə(r) How to pronounce hydrator (audio)
plural -s
: one that hydrates

Examples of hydrate in a Sentence

Verb lotions and creams that hydrate the skin Drink fluids to hydrate the body.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Verb
There is a major heat risk for outdoor activity, and those working outdoors in the afternoon should take extra precaution to hydrate and not overheat during normal activities. — Sean MacAday, Sacbee.com, 10 Aug. 2026 This lightweight, fragrance-free formula uses hyaluronic acid to hydrate and blurring polymers to soften the appearance of pores, helping her makeup glide on more evenly without leaving my mom’s skin feeling greasy or heavy. — Olivia Cefalu, InStyle, 9 Aug. 2026 Staying hydrated, after all, is necessary for optimal brain function and energy. — Kirsten Nunez, Martha Stewart, 8 Aug. 2026 Plus, watering early in the day gives the turf grass time to fully hydrate before the heat of the day sets in. — Megan Hughes, Better Homes & Gardens, 8 Aug. 2026 See All Example Sentences for hydrate

Word History

Etymology

and Noun (2)

First Known Use

Noun (1)

1802, in the meaning defined above

Verb

1846, in the meaning defined at transitive sense 1

Time Traveler
The first known use of hydrate was in 1802

Phrases Containing hydrate

Rhymes for hydrate

See All Rhymes for hydrate

Browse Nearby Words

hydrase
hydrate
hydrated alumina
See all Nearby Words

Cite this Entry

“Hydrate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrate. Accessed 12 Aug. 2026.

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Kids Definition

hydrate

1 of 2 noun
hy·​drate ˈhī-ˌdrāt How to pronounce hydrate (audio)
: a compound formed by the union of water with some other substance
a hydrate of copper sulfate

hydrate

2 of 2 verb
hydrated; hydrating
1
: to cause to take up or combine with water or the elements of water
2
: to supply with sufficient amounts of fluid or moisture
hydration
hī-ˈdrā-shən How to pronounce hydrate (audio)
noun

Medical Definition

hydrate

1 of 2 noun
hy·​drate ˈhī-ˌdrāt How to pronounce hydrate (audio)
: a compound (as Glauber's salt) formed by the union of water with some other substance

hydrate

2 of 2 verb
hydrated; hydrating

transitive verb

: to cause to take up or combine with water or the elements of water

intransitive verb

: to become a hydrate

More from Merriam-Webster on hydrate

Thesaurus: All synonyms and antonyms for hydrate

Nglish: Translation of hydrate for Spanish Speakers

Britannica.com: Encyclopedia article about hydrate

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