Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
fuscĭna, ae, f. [kindr. with furca], a three-pronged spear, a trident: dant (deo) arcum, sagittas, hastam, clipeum, fuscinam, fulmen, Cic. N. D. 1, 36, 101; as an attribute of Neptune, Suet. Calig. 52; as a weapon of the retiarii, id. ib. 30; Juv. 2, 143; Paul. Sent. 3, 6, 66.