Tool

n.

Heard in Dublin, Cork, Limerick, Westmeath, Galway, Offaly, Waterford, Kildare and Donegal

An annoying, foolish, or obnoxious person.

In use

Yer man Colin is an awful tool when he gets a few jars into him.

Posh English

Our acquaintance Colin is a profoundly tedious idiot when he imbibes a few flagons.

Same phrase, other counties