- stroboscope (n.)
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- "instrument for studying motion by periodic light," 1896, from -scope + comb. form of Greek strobos "a twisting, act of whirling," from PIE *streb(h)- "to wind, turn" (see strophe). Earlier as the name of a similar device used as a "scientific toy" [OED]. Related: Stroboscopic (1846).