dehydration

American  

[dee-hahy-drey-shuhn] / ˌdi haɪˈdreɪ ʃən /

noun

1. the act or process of dehydrating.

2. an abnormal loss of water from the body, especially from illness or physical exertion.

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dehydration Scientific  

/ dē′hī-drā′shən /

1. The process of losing or removing water or moisture.

2. A condition caused by the excessive loss of water from the body, which causes a rise in blood sodium levels. Since dehydration is most often caused by excessive sweating, vomiting, or diarrhea, water loss is usually accompanied by a deficiency of electrolytes. If untreated, severe dehydration can lead to shock.

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Etymology

Origin of dehydration

First recorded in 1850–55; dehydrate + -ion

Example Sentences

WASHINGTON—Supreme Court Justice Samuel Alito was taken to a hospital and given fluids for dehydration last month after attending a dinner in his honor in Philadelphia.

From The Wall Street Journal • Apr. 3, 2026

A spokesperson for the rap star, 31, confirmed to The Times on Wednesday that the artist’s doctors “ultimately identified extreme exhaustion, dehydration, vasoconstriction and low metabolic levels as the cause of her symptoms.”

From Los Angeles Times • Apr. 1, 2026

"People could be dead or dying from dehydration, heat stroke or any other conditions," pilot Omar El Manfalouty told AFP.

From Barron's • Feb. 10, 2026

Palmer ultimately sought care at both the urgent care and the emergency room because she was worried about dehydration.

From Salon • Jan. 8, 2026

“Your skin is still elastic, which means your dehydration isn’t critical yet.”

From "Dry" by Neal Shusterman and Jarrod Shusterman

Related Words

• lack
• scarcity