vbl. sb. [f. FLAN v. + -ING1.] (See quots.)
1849–50. Weale, Dict. Terms, Flanning, the internal splay of a window-jamb.
1852. Raine, North Durham referred to in Dict. Arch. (Arch. Publ. Soc., 1862).
1874. Knight, Dict. Mech., I. 876/2. Flanning. (Building.) The internal flare of a window jamb. The embrasure. Or of a fireplace. Coving.
