noun, feminine/ɛ̃.sɔ.la.sjɔ̃/plural: insolations
sunstroke, insolation (heatstroke caused by an excessive exposure to the sun's rays)
“—Mais vous êtes fou d'aller en Espagne en été; sachez que la chaleur y est torride, insupportable. —Qu'importe, nous nous vêtirons légèrement, ai-je répondu. —Vous attraperez des insolations. —Nous nous coifferons de larges panamas!” — But you are crazy, going to Spain in summer; you know that the heat there is torrid, it's unbearable. ―No matter, we will dress lightly, I responded. ―You'll get sunstroke. ―We'll wear big Panama hats!
Learned borrowing from Latin īnsōlātiōnem.