Dione

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noun Di·o·ne \ ˌdī-ˈō-nē \

Definition of Dione

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 WilfordNew York Times29 Oct. 1980

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First Known Use of dione

1879


-dione

noun suffix -di·one \ ˈdīˌōn \

Definition of -dione

plural -s
:chemical compound containing two carbonyl groups in names of diketones or di-oxo compounds that are not true diketones
  • butanedione
  • 2,6-piperidine-dione

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Origin and Etymology of -dione

International Scientific Vocabulary di- + -one


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