Hungover describes the state of feeling ill after drinking too much alcohol — the headache, nausea, thirst, fatigue, sensitivity to light, and general malaise of the morning after. The physiology is well mapped: dehydration from alcohol’s diuretic effect, acetaldehyde and congener toxicity (worse in dark drinks), blood-sugar dips, electrolyte disturbance, and shattered sleep architecture. “Hungover” is the adjective; the condition is the hangover. Prevention is dose-dependent — pacing, water between drinks, eating beforehand, and above all drinking less; cure is time, fluids, and rest, with no folk remedy surviving rigorous testing. The word’s casualness belies a genuine toxic insult — the body keeps score.