an imaginary card that is given to best friends, once this card is ripped up you are usually not friends with them again... until you tape it back up, if your friend is trustworthy again
do u swear on your friendship card that you love her
A card that is used throughout a tight group of friends that is given to someone in the cardholders time of need. A somewhat "favor" card that is given to someone so that they help you out. Once given away, the only way to gain it back, is to do a favor for the friend.
In the movie "Good Luck Chuck" Dane Cook uses his friendship card to get his friend to date the fat/gross/ugly girl by the pool to see if she would marry him.