Bog

n.

Heard in Dublin, Antrim, Tyrone, Donegal and Sligo

1) countryside. 2) toilet. Also: Anywhere outside Dublin's city limits.

In use

I'm off to the bog for a pony. Once you're past Firhouse you're out in the bog.

Posh English

I am departing for the lavatory. Once you pass Firhouse you are out in the countryside.

Same phrase, other counties