he·​lio·​graph ˈhē-lē-ō-ˌgraf How to pronounce heliograph (audio)
: an apparatus for telegraphing by means of the sun's rays flashed from a mirror
heliograph transitive verb

Word History


International Scientific Vocabulary

First Known Use

1877, in the meaning defined above

Time Traveler
The first known use of heliograph was in 1877

Dictionary Entries Near heliograph

Cite this Entry

“Heliograph.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heliograph. Accessed 28 Jan. 2023.

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