During a conversation on the phone, it is the act of simulating a "High 5" by pressing '5' on the keypad at the appropriate moment.
Joe: So where did you go with that girl last night?
Moe: Back to my place.
Joe: Brown chicken, brown cow?
Moe: You know it!
Joe: PHONE 5!!!
*Joe presses 5 key*
Moe: Back to my place.
Joe: Brown chicken, brown cow?
Moe: You know it!
Joe: PHONE 5!!!
*Joe presses 5 key*
by EJO86 July 17, 2009