Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† sōry, ĕos, n., = σῶρυ, a kind of ore, ink-stone, sory, Plin. 34, 12, 29, § 117; 34, 12, 30, § 120; Cels. 6, 9, 23.