It means Chill The F*** Down, or
Calm The F*** Down, usually used when one person gets
mad at something simple, which wasn't meant to insult. Also used to
calm someone down before a Beef.
#1 "
Dude, Stace went to the Movies with Robert"
#2 "WHAT?!?!?!?"
#1 "
Dude, CTFD she went with her Posse"
"Yo mamma so stupid she put
paper on the television and called it paper view!"
"What you say 'bout my mamma?!?!"
"CTFD, It was a harmless joke"