heatstroke
From Longman Dictionary of Contemporary EnglishRelated topics: Illness & disabilityheatstrokeheat‧stroke /ˈhiːtstrəʊk $ -stroʊk/ noun [uncountable] MIfever and weakness caused by being outside in the heat of the sun for too long → sunstrokeExamples from the Corpusheatstroke• Guys would pass out from heatstroke.• As the victim's temperature rises higher and higher, they suffer internal heatstroke and all their organs gradually fail.• After a heroic week of earth moving, he went down with heatstroke.