From Longman Dictionary of Contemporary Englishmansardman‧sard /ˈmænsɑːd $ -ɑːrd/ (also mansard roof) noun [countable] technical TBCa roof whose lower part slopes more steeply than its upper part
Examples from the Corpus
mansard• Houses with a mansard roof can not be converted, as the first floor rooms are already in the roof space.• The building is covered by a reinforced concrete roof of mansard profile, which houses the seventh storey. 