1) Aid for night photos, once 2) Flash 3) Flash bulb 4) Flash lamp 5) Flashgun 6) Lamp 7) Outmoded camera accessory 8) Photoflash 9) Photographic equipment 10) Picture-taking item Found on https://www.crosswordclues.com/clue/flashbulb
one-time light bulb giving a single bright burst of light, used in photography. See flash lamp.[2 related articles] Found on http://www.britannica.com/eb/a-z/f/34
a glass bulb, filled with oxygen and aluminum or zirconium wire or foil, which, when ignited electrically, burns with a brilliant flash to provide momentary illumination of a subject. Found on https://www.infoplease.com/dictionary/flashbulb