Flare (noun)

1. A sudden burst of flame or light.
2. A sudden and temporary increase in intensity or prominence of something.
3. A torch or other device used to produce a bright light for a short period of time, typically as a signal.

Origin:

Late middle english: from old french flere "weep, grieve", based on latin flare "blow".

Examples:

1. The flares illuminated the runway.
2. A flare of pain shot through his arm.
3. He lit a flare to signal for help.
4. The flares provided temporary lighting during the blackout.
5. The flare of anger in his eyes was unmistakable.