abbreviation for "For Fuck's Sake". used to express major exasperation towards a person or situation that is bothering someone. often used in online video game chat messages or text messages.
"When is doom arena scheduled again?"
"FFS, you neverlisten to what I say!!!!"
FFS in the car and truck world typically means (FAR FROM STOCK ).
that of course is refering to lots of after market (not stock) parts that are added for gains in horse-power or tourke.
they can also be added for visual appeal of for added comfort