This is a term used by Nigerians to express surprise or excitement
guy1:ASUU has called off the strike
guy2:Mad oo!
by Sarnou March 28, 2020
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An exclamation made when someone says something too unbelievable or exciting
Some random chick: My boyfriend promised to get me the new iPhone 11

Some random chick's friend: Mad oo
by jsyk I'm here July 20, 2020
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