barrel vault <p style="font-weight: 400;">Vaults of plain, semicircular cross section supported by parallel walls or arcades.</p> <p style="font-weight: 400;">Source: Art and Architect Thesaurus</p> <p style="font-weight: 400;"> <a href="http://vocab.getty.edu/page/aat/300014426">http://vocab.getty.edu/page/aat/300014426</a></p>