spec·​tro·​he·​lio·​gram ˌspek-trō-ˈhē-lē-ə-ˌgram How to pronounce spectroheliogram (audio)
: a photograph of the sun that is made by monochromatic light and shows the sun's faculae and prominences

Word History

First Known Use

1905, in the meaning defined above

Time Traveler
The first known use of spectroheliogram was in 1905

Dictionary Entries Near spectroheliogram

Cite this Entry

“Spectroheliogram.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spectroheliogram. Accessed 31 Mar. 2023.

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