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.

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 km Compare Deimos

Scientific definitions for phobos

Phobos
[ fōbəs ]

The larger and inner of the two planetary satellites of Mars.