Lewis & Short

ăbolla, ae, f. [ἀμβολή = ἀναβολή, prop. a throwing back and around], a robe of thick woollen stuff worn by soldiers, philosophers, etc. (called in Verg. A. 5, 421, duplex amictus; v. Serv. ad h.l.): toga detracta est et abolla data, Varr. ap. Non. 538, 16: purpurea, Suet. Calig. 35.
Of philosophers, Mart. 4, 53; 8, 48; Juv. 4, 76 al.: facinus majoris abollae, i. e. a crime committed by a deep philosopher, Juv. 3, 115.