søk opp hvilket som helst ord, som basic bitch:
A person who is a friend, only when your other friends are not present.

Also referred to as a "number two". Any social networking site has a Top Friends, and the number is your next best friend.
"Well, John isn't here, so I guess I'll have to talk to my fill-in friend."

"Amy had to go to the concert, so I guess it's just me and the number two."
av NOT a fill-in friend. 3. mai 2009

Words related to fill-in friend

2 conditional-friend fillin friend number 2 number two