Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
tōmentum, i, n., a stuffing for cushions (e. g. of wool. hair, feathers, straw, etc.), cushioning, Plin. 8, 48, 73, § 192; 19, 1, 2, § 13; 27, 10, 61, § 88; Varr. L. L. 5, § 167 Müll.; Suet. Tib. 54; Tac. A. 6, 23 med.; Mart. 14, 159 in lemm.; 14, 160 in lemm.; 14, 162; App. Mag. p. 276, 14; cf. Becker, Gallus, 2, p. 240 (2d edit.).