FYFI 

For Your Fucking Information

FYFI, I don't like you. I never did.

FYFI by lou, urban dict. September 19, 2008

FYFI 

Freshman Year Fuck It- feeling of freshman year of college when you are willing to do anything.

Student 1: Hey man how late where you out last night?

Student 2: I got back to my dorm at 6
Student 1: Didn't you have an 8am?
Student 2: Yeah but FYFI

FYFI by rmattr September 15, 2016

Fyfing 

Is the processing in which a individual smokes residual crystal meth on the stem of a crack pipe to insignificantly increase ones high.

Zac was being overly desperate, so he snuck away and started fyfing the pip. Sado

Fyfing by Faybo March 9, 2014