noun Psychology.
  1. an apparatus for use in exposing visual stimuli, as pictures, letters, or words, for an extremely brief period, used chiefly to assess visual perception or to increase reading speed.

Origin of tachistoscope

1905–10; < Greek táchist(os), superlative of tachýs swift + -o- + scope
Related formsta·chis·to·scop·ic [tuh-kis-tuh-skop-ik] /təˌkɪs təˈskɒp ɪk/, adjective
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British Dictionary definitions for tachistoscope


  1. an instrument, used mainly in experiments on perception and memory, for displaying visual images for very brief intervals, usually a fraction of a second
Derived Formstachistoscopic (təˌkɪstəˈskɒpɪk), adjectivetachistoscopically, adverb

Word Origin for tachistoscope

C20: from Greek takhistos swiftest (see tachy-) + -scope
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

tachistoscope in Medicine


  1. An apparatus that projects a series of images onto a screen at rapid speed to test visual perception, memory, and learning.
Related formsta•chis′to•scopic (-skŏpĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.