heliometer

noun

he·​li·​om·​e·​ter ˌhē-lē-ˈä-mə-tər How to pronounce heliometer (audio)
: a visual telescope that has a divided objective designed for measuring the apparent diameter of the sun but also used for measuring angles between celestial bodies or between points on the moon
heliometric
ˌhē-lē-ō-ˈme-trik How to pronounce heliometer (audio)
adjective
heliometrically
ˌhē-lē-ō-ˈme-tri-k(ə-)lē How to pronounce heliometer (audio)
adverb

Word History

Etymology

French héliomètre, from hélio- heli- entry 1 + -mètre -meter

First Known Use

1753, in the meaning defined above

Time Traveler
The first known use of heliometer was in 1753

Dictionary Entries Near heliometer

Heliolitidae

heliometer

heliometry

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Cite this Entry

“Heliometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heliometer. Accessed 22 Nov. 2024.

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Britannica.com: Encyclopedia article about heliometer

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