It means Be quiet in a ruder tone or like you're being surprised about something.
"And then- Blah blah blah blah"
"Shut up."

Or

"I got into 100% on that test that everyone failed."
"Shut up! No way. You're telling me you got 100% on that test? Shut up."
by K o o k i e May 27, 2020
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Shut up is mostly for your write but i wont say your right
Girl : I hate having you as an ugly boyfriend
Boy: Shut up
by Liliana cruz December 17, 2017
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Close your mouth and don’t make noise what so ever!
I told my friend to shut up! She glares

for a moment then left.
by Sksksksksksksksks May 19, 2019
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1. A word used to say be quiet when someone is being straight-up annoying.
2. A word used when someone has been proved wrong
3. A lame comeback.
1.
James: Can you stop touching me
Steve: *finger1/2 cm away from james* I'm not touching you.
James: SHUT UP!

2.
Laura: It's spelled B-E-L-I-V-E
Clara: No, it's B-E-L-I-E-V-E
Laura:Google it!
Google:*says Clara is correct*
Clara: I told you!
Laura: Shut up!
by hamilfan_for_life November 30, 2020
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