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Phobos

[foh-buh s, -bos]
noun
  1. Also Pho·bus [foh-buh s] /ˈfoʊ bəs/. Classical Mythology. a son and attendant of Ares and the personification of a fear held to possess armies and cause their defeat.
  2. Astronomy. one of the two moons of Mars.
Compare Deimos.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for phobos

Phobos

noun
  1. the larger of the two satellites of Mars and the closer to the planet. Approximate diameter (although it has an irregular shape): 23 kmCompare Deimos
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
phobos in Science

Phobos

[fō′bəs]
  1. The larger and inner of the two planetary satellites of Mars.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.