Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
lanterna (ante-class. and later lā-terna), ae, f. [Gr. λαμπτήρ, root in λάμπω; cf. Lat. limpidus, lepor, lepidus, lĕpus], a lantern, lamp, torch: a portu illic nunc cum laterna huc advenit, Plaut. Am. prol. 149: laterna Punica, id. Aul. 3, 6, 30: linea lanterna, Cic. Att. 4, 3, 5: hic caulis olebit lanternam, Juv. 5, 88; Plin. 11, 16, 16, § 49.