short for "fucking funny" used when something is so funny you actually laugh about it for days
"Have you seen Achmed the dead terrorist?"
"Yes! It's so fuckny!"
When you are short on time or words, and something is fucking funny. Combine the two.
That was some fuckny shit son.
When somebody is referred to as a 'dick urkel motherfucker.
What a dick urkel motherfucker, what a fuckni.