Word Study
tachistoscope
CIDE DICTIONARY
tachistoscope, n. [Gr. ta`chistos, superl. of tachy`s swift + -scope.].
An apparatus for exposing briefly to view a screen bearing letters or figures. It is used in studying the range of attention, or the power of distinguishing separate objects in a single impression. [Webster 1913 Suppl.]
OXFORD DICTIONARY
tachistoscope, n. an instrument for very brief measured exposure of objects to the eye.
Derivative
tachistoscopic adj.
Etymology
Gk takhistos swiftest + -SCOPE
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