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

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now