The story
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A specialized, precise light source that produces extremely brief, highly controlled flashes of light at a known, adjustable rate; it essentially combines the functions of a stroboscope (a tool used to make moving parts appear stationary) with a focused torch or lamp. Full definition →
Etymology from Wiktionary, CC BY-SA 4.0.