Bob: "I can't believe Ashley (skinny, popular girl) put me in the Friend Zone! I was nice to her all this time, and she still says we're just 'friends!' But friendship is what a a romantic relationship is built on!"
Kaylee (overweight, average-looking girl): "Well Bob, you and me are friends too, and I'm single."
Bob: I... uh... erm..... but I don't wanna ruin our friendship Kaylee.
A needy roommate, classmate, relative, or other associate who impedes your ability to make friends by insisting on being part of any new relationship you try to make. The friend blocker stands next to you while you are meeting new people and makes clear that the blocker is part of any new friendship.
Dillon is introducing himself to Jeremy, a new guy on the dorm floor. Dillon's roommate is a friend blocker, so he walks up beside Dillon and says, "Dillon, my man, who's our new friend?" Then the roommate stands immediately next to Dillon for the duration of the conversation.
When you denounce a friend, or group of friends after a serious falling out. More serious than a simple argument. Usually involves some sort of betrayal from an old friend. Often leads to a cleansing of people who you realized aren't really your friends.
Divorcee: "Scott banged my girlfriend, And the crew thought it was cool"
Friend: "Oh man that sucks, do you still talk with them?"
Divorcee: "Nah man, I friend divorced the whole lot of em, the're shite in a bucket"
Friend: "and what about her?"
Divorcee: "Well let's just say we are not getting married"