- heliograph⇄heliograph, noun, verb.
- heliograph⇄noun heliographer.
- heliograph⇄noun 1. a device for signaling by means of a movable mirror that flashes beams of sunlight to a distance.
2. an apparatus for taking photographs of the sun.
3. a printing image obtained by a process in which a specially sensitized plate is - heliograph⇄v.t., v.i. to signal by heliograph.