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


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noun suffix

plural -s
: chemical compound containing two carbonyl groups
in names of diketones or di-oxo compounds that are not true diketones

Word History


Noun suffix

International Scientific Vocabulary di- + -one

First Known Use


1879, in the meaning defined above

Time Traveler
The first known use of Dione was in 1879

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Dictionary Entries Near Dione

Cite this Entry

“Dione.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Dione. Accessed 21 Sep. 2023.

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