What does “canicule” mean in French?

La canicule is a heatwave, and the word is a dog. It comes from Latin canicula, “little dog,” the Roman name for Sirius in the constellation Canis Major. Sirius rose with the sun during the hottest weeks of the year, so the Romans called them dies caniculares — the same “dog days” English still uses. French kept the dog and dropped the days.

In French forecasting canicule is a technical threshold rather than just “very hot”: both daytime and night-time temperatures have to stay above set limits for several days, which is why bulletins pair it with vigilance levels. This report carries the vocabulary that travels with it — les urgences (A&E, the ER), le plan bleu (the care-home heat protocol written after the deadly 2003 canicule), and un malaise, the all-purpose French word for a fainting spell or a funny turn.