O pọ is a complete sentence as short as it is. O pọ/ opor is also written as o por. Which is the wrong spelling.
The correct spelling of o por is, O pọ. There is no “r” after it.
Anyway, o pọ translates to, “it is plenty”.
It is a Yoruba slang that you will most likely hear in the mouth of youths living in South West Nigeria.
Sometimes, they will call, o pọ yẹ yẹ! Or another popular extension of o por/opor is, “ko po ke!”.
All in all, they are slangs.
But o pọ/opor is a normal Yoruba statement that means, “it is plenty”.