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

Definition of Dione

 (Entry 1 of 2)

: 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


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


1879, in the meaning defined above

History and Etymology for Dione

Noun suffix

International Scientific Vocabulary di- + -one

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Time Traveler for Dione

The first known use of Dione was in 1879

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