A Nigerian term used when you agree with something or you think something is really cool or makes sense. The last letter can be lengthened to show higher degree of coolness.
E.G: TMZ: Amber Rose's sex tape out now
Wiz Khalifa: Osheyyyy...
or
Kanye: Scott, Kim K now gives free bj's
Scott: Osheyyyyy.. correct girl
163👍 21👎