1) If you hear someone say "hey oh" you have to say it back.
A greeting.

2) When someone says "hey oh" in a large group of people, everyone has to reply by saying it back.
Usually used jokingly after something raunchy is mentioned.
Example 1:
Person 1: (name)!
Person 2: hey oh!
Person 1: hey oh!
Person 2: whassssssuppppp?!

Example 2:
Person 1: She talks shit behind everyone's back.
Person 3: ... and then she tries to act all nice and shit.
Person 2: I heard she can fit a whole soap on a rope up her cooter.
Person 1: haha, hey oh.
Person 2: hey oh.
Person 3: hey oh.
by cass! December 24, 2007
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Cocaine. inspired by the Red Hot Chili Peppers song "Snow (Hey Oh)"
"I got your hey oh, now listen what I say, oh"
by Mr. Ho7987887 January 16, 2012
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A reaction to a pick-up line, comeback, burn, or diss that was, at first thought, great, but upon further examination revealed itself to be a) stupid, b) creepy, or c) just plain tragic. Usually starts with great enthusiasm only to die down very quickly.
Guy 1: Boy your mama's so fat they had to use an atomic bomb to make a crater large enough to bury her in!

Guy 2: HEY-oh.
by A NONY MOUSE October 21, 2014
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Agreeing with someone to make fun of them.
Bob: My phone never sends text messages.
Me: Well your phone sucks
Bob: Whatever, I like my phone
Me: Oh i know hey...
by Bdjahnke November 11, 2008
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