MARYBOROUGH, a borough, market, and post town, and the affizes town to Queen's county, in the province of Leinster, in Ireland; so called in honour of Mary queen of England, who reduced this part of the country to shore-ground by act of parliament 6th and 7th Philip and Mary. It is governed by a burgomaster and bailiffs, and has a barracks for a troop of horse. It formerly returned two members to parliament. It is distant from Dublin 40 miles. N. Lat. 53.0. W. Long. 7. 20.