ENGLISH
REFERENCE

dehydration

n. uncountable
B2 Upper Intermediate US //ˌdihaɪˈdɹeɪʃən// UK //dˌiːhaɪdɹˈeɪʃən// de·hy·dra·tion

n. a condition where your body loses more water than it takes in. It can make you feel tired, thirsty, or dizzy.

n. a physiological state resulting from an excessive loss of body water. Often used to describe the medical condition or the process of removing moisture from a substance.


SIMPLE

Drinking water during a long hike helps prevent dehydration.

CONTEXTUAL

The athlete was treated for severe dehydration after competing in the marathon under the midday sun.

COMPLEX

Clinical dehydration can lead to electrolyte imbalances and impaired cognitive function if not addressed promptly with oral rehydration salts or intravenous fluids.

Synonyms
Origin

From de- + hydration.

Usage

Typically uncountable when referring to the medical state; can be countable in technical contexts referring to specific chemical processes.

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