A groin vault or groined vault (also sometimes known as a double barrel vault or cross vault) is produced by the intersection at right angles of two barrel vaults. The word groin refers to the edge between the intersecting vaults; cf. ribbed vault. Sometimes the arches of groin vaults are pointed instead of round.
A. D. F. Hamlin College Histories of Art History of Architecture (New York, NY: Longmans, Green, and Co., 1915)
Courtesy the private collection of Roy Winkelman