Belching at a formal dinner is loutish behavior.

When Brad drank too much alcohol, his behaviour would often become loutish, when he lost control of his mouth and his judgement.

Thomas never apologized for his loutish behaviour, so throughout his college years, he failed to earn loyal friendships.

In the manner of a lout, a stupid, violent, ignorant, lazy and uselessgoon.

An Irish kern is either an Irish foot solider or a loutish person (reference: "kern" on http://www.answers.com).

That loutish and naive 6'-3" yokel is one of the Yokum clan of hillbillies from Dogpatch, Arkansas.