stroboscope

stro·bo·scope

noun \ˈstrō-bə-ˌskōp\

Definition of STROBOSCOPE

: an instrument for determining the speed of cyclic motion (as rotation or vibration) that causes the motion to appear slowed or stopped: as a : a revolving disk with holes around the edge through which an object is viewed b : a device that uses a flashtube to intermittently illuminate a moving object c : a cardboard disk with marks to be viewed under intermittent light

Origin of STROBOSCOPE

Greek strobos whirling + International Scientific Vocabulary -scope

First Known Use: 1896