Where does the last name Dowdy come from?

The proud- and noble- Irish surname of "Dowdy" derives from the ancient Gaelic language word "dubh", meaning dark-complexioned or black. First found recorded in County Mayo, they were the traditional Princes of Hy-Fiachra in Connaught.
The Dowdy surname is of Northern Ireland origin. It comes from O Dubhda which ultimately means "black". Related names are O'Dowd, Dowd, Dawdy, Dowdy, O'Dowda and Dowds, Doody and Duddy. There is a coat of arms assigned to the O'Dowd name, and there is another for Dowdy which may or may not be accurate.