"Oirish" is a term coined by amused Irish natives to describe anything associated with the tourist cult of Ireland that paints it as the land of shamrocks, blarney stones, leprechauns, and Guinness.
It can also be used to describe anyone who despite many generations in the new world and questionable Irish ancestry constantly proclaims themselves to be Irish. This can range from an innocent baseball cap with a shamrock on it to a drunken twit in a kilt idiotically greeting everyone with a faux accented "top o' the mornin' to yah laddie".
Phill : Oh look it's J. do you see that the twit brought himself a shillelagh.
Robert : Yeah I see. It's great little costume he has there you'd almost think the oirish twit was auditioning for a part on Ballykissangel.
A word used to describe or in response to a situation, circumstance, or happening that needs only one word. It can elaborate the deep seeded thoughts that people truly feel.