Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
amb-ĕdo, ēdi, ēsum, 3 (pres. 3d pers. ambest, Paul. ex Fest. p. 4 Müll.), v. a., to eat or gnaw around, and with an extension of the idea (cf.: adedo, aduro, accīdo), to waste, consume (very rare; not in Lucr. 5, 396, where the correct read. is lambens; v. Lachm. ad h. l.): flammis ambesa Robora, Verg. A. 5, 752: ambesas absumere mensas, id. ib. 3, 257: vis locustarum ambederat quidquid herbidum, Tac. A. 15, 5; so Dig. 41, 1, 38.