something uncool or not good.

When the word no just doesn’t seem expressive enough.

Meaning utter disagreeance with the situation at hand.
“So I was driving down the road and suddenly a deer wanders in front of my car and I’m like ‘OI NAH’ and hit the breaks to avoid hitting it.”
by Shananniegans August 28, 2018
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Affirming ones statement, but gaining the attention of the other person in the conversation to continue ones point.
Lets go to the pub, but "Nah Oi" not that one.
by Hugo Vag October 25, 2010
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