Dione

noun
Di·o·ne | \ˌdī-ˈō-nē \

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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Dictionary Entries near Dione

Diomede Islands

Diomedes

-dione

Dione

dionin

dionise

Dionysia

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The first known use of Dione was in 1879

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