Deimos

American

[dahy-mos] / ˈdaɪ mɒs /

noun

an ancient Greek personification of terror, a son of Ares and Aphrodite.
Astronomy. one of the two moons of Mars.

Deimos British

/ ˈdeɪmɒs /

noun

the smaller of the two satellites of Mars and the more distant from the planet. Approximate diameter: 13 km Compare Phobos

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Deimos Scientific

/ dē′mōs,dā′- /

The satellite of Mars that is second in distance from the planet.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Researchers believe micrometeorites striking Mars' moons, Phobos and Deimos, may throw dust particles into space.

From Science Daily • May 11, 2026

The spacecraft will spend three years around Mars conducting science operations to observe Phobos and Deimos.

From Salon • Dec. 29, 2023

While Earth’s Moon has many visitors – big and small, robotic and crewed – planned for 2024, Mars’ moons Phobos and Deimos will soon be getting a visitor as well.

From Salon • Dec. 29, 2023

Recently it captured high-resolution images of Deimos, the smaller of the two Martian moons.

From New York Times • May 29, 2023

We find them throughout the inner solar system—from Mercury, closest to the Sun, to cloud-covered Venus to Mars and its tiny moons, Phobos and Deimos.

From "Cosmos" by Carl Sagan

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023