dehydrate

verb

de·​hy·​drate (ˌ)dē-ˈhī-ˌdrāt 

dehydrated; dehydrating; dehydrates

transitive verb

1

a

: to remove bound water or hydrogen and oxygen from (a chemical compound) in the proportion in which they form water

b

: to remove water from (something, such as a food)

2

: to deprive of vitality or savor

intransitive verb

: to lose water or body fluids

dehydrator

(ˌ)dē-ˈhī-ˌdrā-tər 

noun

Did you know?

Dehydrating food is a good way to preserve it; raisins, which are dehydrated grapes, are a good example. Dehydration through industrial processes makes it possible to keep food even longer and store it in a smaller space. Freeze-drying produces food that only needs rehydration—that is, the addition of water—to restore its original consistency. Runners, cyclists, and hikers fearful of dehydration seem to be constantly hydrating themselves nowadays, sometimes even using a shoulder pack with a tube going straight into the mouth. Dehydrate can also be used for making something "dry" or "lifeless;" thus, a dull teacher can dehydrate American history, and an unimaginative staging can dehydrate a great Shakespeare play.

Synonyms of dehydrate

• undermine
• weaken
• drain
• desiccate
• exhaust
• petrify
• wear

Examples of dehydrate in a Sentence

Salt dehydrates the meat and keeps it from spoiling.

Athletes drink lots of water so they don't dehydrate.

Exercising in this heat will dehydrate you.

Recent Examples on the Web

The treatment for a cramp may vary depending on the root cause; for instance, if an athlete is cramping because they’re dehydrated, then the best remedy would be IV fluid or electrolyte water. — Chantelle Lee, Time, 26 June 2026

They can get dehydrated and overexposed to the sun and are unable to cool down. — Janet Loehrke, USA Today, 25 June 2026

Never, ever leave your pet unattended in a hot car and know that pets also get dehydrated quickly, so have plenty of fresh cool water on hand. — David Yeomans, CBS News, 25 June 2026

By quenching dryness, the formula delivers instantly glowy skin and smooths the appearance of fine lines (which are more prominent when skin is dehydrated). — Sophie Wirt, InStyle, 22 June 2026

Word History

First Known Use

1876, in the meaning defined at transitive sense 1a

Kids Definition

dehydrate

verb

de·​hy·​drate (ˈ)dē-ˈhī-ˌdrāt 

1

: to remove water from (as foods)

2

: to lose water or body fluids

dehydration

ˌdē-ˌhī-ˈdrā-shən

noun

Medical Definition

dehydrate

verb

de·​hy·​drate (ˈ)dē-ˈhī-ˌdrāt 

dehydrated; dehydrating

transitive verb

1

: to remove bound water or hydrogen and oxygen from (a chemical compound) in the proportion in which they form water

2

: to remove water from (as foods)

intransitive verb

: to lose water or body fluids

dehydrator

-ˌdrāt-ər 

noun