Meaning of photochronograph

pho•to•chron•o•graph

Pronunciation: (fō"tu-kron'u-graf", -gräf"), [key]
— n.
  1. a device formerly used for taking a series of instantaneous photographs of a rapidly moving object.
  2. a picture taken by such a device.
  3. a chronograph in which the tracing or record is made by a pencil of light on a sensitized surface.
  4. an instrument for measuring small intervals of time by the photographic trace of a pencil of light.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.