Mimas

noun

Mi·​mas ˈmī-məs 

astronomy

: the seventh largest satellite of Saturn with a diameter of approximately 250 miles (400 km) characterized by a single enormous crater

The majestic saturnian rings, having beguiled astronomers for centuries, are targeted for intense study. Saturn's smaller satellites—such as Mimas, nicknamed the "Death Star," and Iapetus, with its strange, organic-marked sur-face—will give up much of their secrets to Cassini.

—Louis D. Friedman, The Planetary Report, March/April 1994

Word History

First Known Use

1847, in the meaning defined above

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