Plain English Meaning

Something you eat or drink that makes you urinate more often, causing your body to lose fluid faster than usual.

Full Definition

A substance that increases the production of urine by the kidneys, causing the body to lose water and electrolytes faster than normal. Common diuretics include caffeine (coffee, tea, many soft drinks, energy drinks) and alcohol.

Context Anchor

Seen in aeromedical discussions about dehydration, heat, alcohol, caffeine, and medication use before or during flight.

Derivation

From Greek 'diouretikos', meaning 'promoting urine'. The root 'oûron' means urine. Knowing this helps because the word's whole purpose is to describe substances that pull water out of the body through urination.