A phrase to show your acceptance and/or and or approval of an idea or event. Or... if used in certain situations a way of expressing your discontent caused by a person's actions, ideas, or events.
a)1: what's good my homie?

2: not much man, just been chillin.

1: that's what's up.

b) so you're gonna side with them over me, huh? That's what's up.
by KingD303 April 10, 2016
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a generlaised greeting, can be used in most situations but has only one correct response - i hate bottles
by idiot cat November 28, 2004
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Just trying to fucking see wHaTs uP, fuck >:O
Me: What’s up?

Julissa: What do u mean what’s up see

Everytime I text u

It’s like I have to have a reason

Me: Relax all I said was What’s up to see how you were doing
by Anon9173638 April 26, 2020
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The most lazy, and unoriginal way to engage a conversation. Used by people who are bored with whom they are talking to, or have nothing else to say.
by Samuek July 22, 2008
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Used to mean "she/he/you is/are very attractive and I would very much enjoy making love to you." It is derived from "A Night at the Roxbury"
Steve: What's up? What's up? What's up? What's up? What's up?
Doug: Steve, slow down.
Steve: I can't help it man, it's hottie overload.
Doug: Just pace yourself.
Steve: Ok... What's up?... 2, 3, 4. What's up?... 2, 3, 4...
by Tonberry2000 April 22, 2009
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An interrogative expression used to request a clarification or repetition of something previously said. Used in place of "what?"
Person 1: "You're not paying attention to me."

Person 2: "What's up?"
by Ian May 3, 2004
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