'Chronoscope' definitions:

Definition of 'chronoscope'

(from WordNet)
noun
An instrument for accurate measurements of small intervals of time

Definition of 'Chronoscope'

From: GCIDE
  • Chronoscope \Chron"o*scope\, n. [Gr. ? time + -scope.] An instrument for measuring minute intervals of time; used in determining the velocity of projectiles, the duration of short-lived luminous phenomena, etc. [1913 Webster]