gallo-nitrate|ˌgæləʊˈnaɪtreɪt| [f.gallo-= gallic a.2 + nitrate.] A combination of gallic and nitric acids with a base. 1841Fox-Talbot Patent SpecificationNo. 8842 Take a sheet of iodized paper and wash it over with this gallo-nitrate of silver.1854J. Scoffern in Orr's Circ.Sc.Chem. 89 Gallo-nitrate of silver.