Phobos

[ foh-buh s, -bos ]
/ ˈfoʊ bəs, -bɒs /

noun

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.
Astronomy. one of the two moons of Mars.
Compare Deimos.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for phobos

Phobos
/ (ˈfəʊbɒs) /

noun

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

Science definitions for phobos

Phobos
[ fōbəs ]

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.