Noun or verb depending on how it's used
The Sup Nod is the sudden up-down movement you make with your head when you see someone and wish to greet them, as if to say "Sup."
You can say "Sup" or "Wassup" or "Hey" as you do it.
You do not necessarily need to know the person to which you are giving the Sup Nod to. It's just a way to say hey.
The Sup Nod can also be used when you catch someone looking at you and you want them to stop.
Some use it as a way to let the shawties know you lookin
Shelby-Did you see Sydney at the party?
Mimi-Yea, she was with Karen. I gave 'em the Sup Nod.
Jamila-That weird boy is staring hard
Shelby-Just give him the Sup Nod
Kevin-Bruh, did you see that shawty over there?! I was tryna give her the Sup Nod.
Ishmael-Ay bruh she's coo
a nod that gives encouragement and/or utter embarassment to the recipient. these nods orientated from ancient indian folk-law and may be used for any occassion. The "can i have your number nod" and the "i really don't care about the troubles in your life nod" are seen to be the most popular of this kind.
Mary passed Cory in the corridor they both exchange the sup nod, before clearing off