populous UK /ˈpɒpjʊləs/US /ˈpɑpjələs/ adjective4 •Having a large population.China is the most populous country in the world. •Spoken by a large number of people.Chinese is the most populous language. •Densely populated.The Nile delta is a populous region. •Crowded with people.Airport departure halls are often populous places during the rush hours. formsmore populous · most populous