Heliograph
Pronunciation: /ˈeɪtʃˈɛɫioʊˈɡɹæf/
Heliograph (noun)
- A device that uses mirrors to send messages using sunlight flashes.
Examples
- The heliograph was used to send messages across the desert.
- Soldiers relied on the heliograph for communication in remote areas.
Common collocations: use a heliograph, rely on a heliograph, heliograph signal