Man o man?

Just saw this on PYC. ‘Man o man i ni ganslo.’ ‘Let’s cancel.’
What’s the translation of ‘man o man’? Keep seeing it in various contexts and can’t quite work it out.

Man a man = might as well

A variant you might encounter in the deep south is the wonderful if somewhat whimsical man a man a mwnci.

“Ti moyn mynd i’r Deri?”
“Man a man a mwnci.”


Does that translate to “going to see a man about a dog”? Not in the literal sense.