verb. 1) to tell someone to "chill"; relax, fall back. 2) commonly used to shut down a stupid remark or completely end a conversation. 3) also used to completely shut down a stupid action another person does. 4) a more stronger form of the verb consists of a double back; i.e. "BACK BACK!". this phrase originated out of the vicinity of Mt. St. Joseph High School in historical Irvington, around the period of 06-07 school years. Its popularity has grown and continues to flourish amongst the Mt. St. Joseph Community and is begining to spread at a rapid paste. Although to term's weight itself is hard to grasp, one must take time as practice to completely master its effectiveness
see corresponding examples from definitions...
1) Stupid Kid: "Hey man guess what I did last weekend?"
Beastly Kid: "What man?"
Stupid Kid: "I got so much ass from these hott chics from _______"
Beastly Kid: "Uh... BACKKK!"
2) Stupid Kid: "Hey man you know who u look like?"
Beastly Kid: "Who?"
Stupid Kid: "Abe Lincoln hahaha"
Beastly Kid: "BACKKK!"
3) Stupid Kid: (decides to go to weight room and put on some rap and dance to it)
Beastly Kids in Weight Room: "BACKKK!"
4) Stupid Kid: "Dude im so nice at basketball"
Beastly Kid: "Uh... Back"
Stupid Kid: "Yo i'd fry you"
Beastly Kid: "BACK BACK!"