A person whose name you know, but you know little to nothing else about them. You both greet one another out of politeness, but rarely, if ever, engage in conversation.
*Mark and Phil (friends) are chatting*
*Jeff passes*
Jeff: "Sup Mark!"
Mark: " Hey Jeff!"
Phil: "I didn't know you were friends with Jeff."
Mark: "We're not really friends, he's just that guy over there."
