FOS

Father over shoulder.

Stop the cybering! FOS!

by AriBigFatBlackGuy November 30, 2009

fos

it could mean also :

Free Open Source

fosdir.com

mean

Free Open Source Directory

by peter edin October 16, 2008

FOS

1) Friggin' Awesome Shit.

2) Friggin' Awful Shit.

meaning varies according to situation. yeah, it doesn't make sense, but at least 2 or 3 people I know have used it.

by bastardface October 21, 2004

FOS

FOS pronounced as False. Meaning Full Of Shit, some one who tell obvious lies to exaggerate there lifestyle.

Alvin so FOS. Why he trying to impress me with all them lies?

by TheRealKennis March 11, 2017

FOS

Fucked over sink

Don’t you just hate when you play fortnite and your mom gets FOS’ed by some random guy

by cw91fos May 13, 2018

FOS

Full of shit.

That pillow lady, was FOS, with all her constant hypocritical judgments.

by Hot Chicky Babe January 31, 2020

FOS

FreedomOfSpeech

Rampage FOS!

by TrumpTheKiđkissingSexoffenđer. November 22, 2020