[1] : The Collaborative International Dictionary of English v.0.48

tachistoscope \tachis"toscope\, n. gr. ta`chistos, superl. of
   tachy`s swift + -scope. physiol.
   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.

[2] : WordNet (r) 2.0

tachistoscope
     n : scientific instrument used by psychologists; presents visual
         stimuli for brief exposures syn: t-scope
see also:
t-scope 

Tachistoscope >> T Words
Tachistoscope, definition of term: Tachistoscope
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