This is the 8520th most frequent French word.
allume
"Allume" means "lights" or "turns on" (in reference to a device, flame, etc.).
In this sentence, 'allume' is used as a verb meaning 'to turn on', indicating the action of activating a light.
Il allume la lumière pour mieux voir.
He turns on the light to see better.
Here, 's'allume' is used in a reflexive form meaning 'ignites' or 'lights itself', describing the process of starting a fire spontaneously or by external action.
Le feu s'allume rapidement dans le bois sec.
The fire ignites quickly in the dry wood.
In this example, 'allume' refers to the action of starting an electronic device, specifically a computer, indicating initiation of use.