Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
spūmĕus, a, um, adj. [spumo], foaming, frothy (poet. and in post-Aug. prose): Nereus, Verg. A. 2, 419: amnis, id. ib. 2, 496: unda, id. ib. 10, 212: torrens, Ov. M. 3, 571: aper, Mart. 14, 221, 2: cumulus undarum, Luc. 9, 798: Rhodanus, Amm. 15, 11, 18: rabies per ora effluit, Luc. 5, 190; cf.: salivae hominis, Prud. στεφ. 1, 101: sucus malorum, Plin. 15, 28, 33, § 109: semen heraclii, id. 20, 19, 79, § 207: color equorum, foamlike, i. e. dappled, Pall. Mart. 13, 4.