Dione

noun
Di·​o·​ne | \ ˌdī-ˈō-nē How to pronounce Dione (audio) \

Definition of Dione

 (Entry 1 of 2)

astronomy
: the fourth largest satellite of Saturn with a diameter of approximately 700 miles (1120 km) Three other new Saturnian moons have been identified in recent years by spacecraft and ground-based telescopes. Two of them are especially intriguing because they lie in essentially the same orbit about 94,000 miles from the planet. The third is a small, asteroid-size satellite moving along in the same orbit much farther ahead of the larger moon, Dione, 234,000 miles from Saturn.— John Noble Wilford, New York Times, 29 Oct. 1980

-dione

noun suffix
-di·​one | \ ˈdīˌōn \
plural -s

Definition of -dione (Entry 2 of 2)

: chemical compound containing two carbonyl groups in names of diketones or di-oxo compounds that are not true diketones butanedione2,6-piperidine-dione

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First Known Use of Dione

Noun

1879, in the meaning defined above

History and Etymology for Dione

Noun suffix

International Scientific Vocabulary di- + -one

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Dione

-dione

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Cite this Entry

“Dione.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Dione. Accessed 20 Jan. 2022.

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