Jacks

n.

Heard in Dublin, Galway and Limerick

The lavatory.

In use

John looked everywhere in the pub for the jacks cause he was dying to go for a piss" "I've been in the jacks all day with the scutters

Posh English

John searched the entire public house for the lavatory as he was desperate to urinate. I have been in the lavatory all day with a severe bout of diarrhoea.

Same phrase, other counties