Pho"to*drome (?), n. [Photo- +
Gr. ? to run.] (Physics) An apparatus consisting of a
large wheel with spokes, which when turning very rapidly is
illuminated by momentary flashes of light passing through slits in a
rotating disk. By properly timing the succession of flashes the wheel
is made to appear to be motionless, or to rotate more or less slowly
in either direction.