dehydration

noun

de·​hy·​dra·​tion ˌdē-ˌhī-ˈdrā-shən How to pronounce dehydration (audio)
Synonyms of dehydrationnext
: the process of dehydrating
especially : an abnormal depletion of body fluids

Examples of dehydration in a Sentence

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.
The resident suffered a kidney injury, dehydration and low blood pressure. — Carol Marbin Miller, Miami Herald, 31 July 2026 As rescuers race to find survivors, thousands shelter in schools, cars and tents, enduring power and water outages while fears grow over heatstroke, dehydration and dwindling emergency food supplies. — Mari Yamaguchi, Los Angeles Times, 30 July 2026 Others have suffered dehydration and diarrheal illnesses during long days in the heat. — ABC News, 29 July 2026 The bacterium Vibrio cholerae kills through dehydration – the watery diarrhea can drain a person to death within hours. — Katrine L. Wallace, The Conversation, 29 July 2026 See All Example Sentences for dehydration

Word History

First Known Use

1840, in the meaning defined above

Time Traveler
The first known use of dehydration was in 1840

Rhymes for dehydration

See All Rhymes for dehydration

Browse Nearby Words

dehydrate
dehydration
dehydrator
See all Nearby Words

Cite this Entry

“Dehydration.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dehydration. Accessed 5 Aug. 2026.

Copy Citation

Medical Definition

dehydration

noun
de·​hy·​dra·​tion ˌdē-hī-ˈdrā-shən How to pronounce dehydration (audio)
: the process of dehydrating
especially : an abnormal depletion of body fluids
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

7 Pairs of Commonly Confused Words

Merriam-Webster’s Great Big List of Words You Love to Hate

Is it 'nerve-racking' or 'nerve-wracking'?

'Sneaked' or 'Snuck': Which is correct?

Why does English have so many silent letters?
See More

Popular in Wordplay

See More

The Longest Long Words List

It's a Scorcher! Words for the Summer Heat

14 Phobias You Probably Haven't Heard Of

How long is a jiffy?

Even More Bird Names that Sound Like Insults (and Sometimes Are)
See More

Popular

See More

7 Pairs of Commonly Confused Words

The Longest Long Words List

It's a Scorcher! Words for the Summer Heat
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
asap street sign
Figure Out These Acronyms ASAP You don't have to be a NASA engineer to get these...
See All