Arch. [ad. L. fornicātiōn-em, f. fornicātus vaulted, f. fornix arch, vault: see -ATION.] An arching or vaulting.
1703. T. N., City & C. Purchaser, 138. Fornication, In Architecture, is an Arching, or Vaulting.
1810. C. James, Mil. Dict. (ed. 3), App. Fornication is an arching, or vaulting.
