Definition of Aberdeen
1a city and seaport in northeastern Scotland, a center of the offshore North Sea oil industry; population 166,900 (est. 2009). 2a town in northeastern Maryland, on Chesapeake Bay; population 13,993 (est. 2008). A major military test range is nearby. 3a city in northeastern South Dakota, a dairy center; population 24,460 (est. 2008).