mosasaur noun1 •A large extinct marine reptile in the family †Mosasauridae, dominant marine predator of the Cretaceous. Mosasaurs are considered to belong to Squamata, the same group that includes lizards and snakes.Mosasaurs could reach lengths of up to 17m and lived mainly in offshore waters of the Late Cretaceous. — 2012 formsmosasaurs
