Source : Webster's Revised Unabridged Dictionary (1913)

Spectroheliograph \Spec`tro*he"li*o*graph\, n. (Astrophysics)
   An apparatus for making spectroheliograms, consisting of a
   spectroscopic camera used in combination with a telescope,
   and provided with clockwork for moving the sun's image across
   the slit. -- {Spec`tro*he`li*o*graph"ic}, a.