a misspelling of "for" when someone is typing a mile a minute, or in capitalised form, the hypothetical compound of oxygen fluoride
by eszett March 09, 2003
1. Furby is FOS
2. Morris: I went for a bit of FOS with apiphonyiernfi
3. Are you going to millys FOS?
2. Morris: I went for a bit of FOS with apiphonyiernfi
3. Are you going to millys FOS?
by jOeFiSh15 October 08, 2008
by Mai327 May 15, 2011
by Donatello Quentinstein Kennedy Ripken Sr. September 09, 2007
n. to describe a person who is 'Full Of Shit', and treats those who try to help them with disrespect.
Person 1: 'I'm not coming to my doctor's appointment today because you didn't tell me I had to pay anything.'
Person 2: 'Don't be such a FOS.'
Person 2: 'Don't be such a FOS.'
by Maria Espia March 18, 2008
by 2451346523562 December 24, 2010
by Archie Black July 11, 2003