Muta mata

n.

Heard in Cork

A fool. Also: a very bright individual who always gets the upper hand and makes the opposition look foolish.

In use

He's a right Muta Mata" "They laughed when that muta mata told them disaster was coming, but he sure got the last laugh when it did.

Posh English

He is a perfect fool. They laughed when that clever fellow warned them of impending disaster, yet he certainly had the final satisfaction when it arrived.