Slash

n.

Heard in Offaly, Cork, Mayo, Sligo, Tyrone and Tipperary

An act of urination, or the urgent physical need to empty one's bladder.

In use

Hurry up will ya, I'm burstin' for a slash!

Posh English

Hurry along if you please, for I am in desperate need of visiting the lavatory!

Same phrase, other counties