I.to take out the backbone, to bone (ante- and post-class.): “congrum, muraenam exdorsua, quantum potes,” Plaut. Aul. 2, 9, 2: “pisces (with desquamare),” App. Mag. p. 301, 3; cf.: “exdorsuare, dorso nudare,” Non. 17, 29: exdorsua dorsum confringe; alii, exime, Paul. ex Fest. p. 79, 12 Müll.
ex-dorsŭo or -dorso , āre, v. a. dorsum; lit., to deprive of the back; hence, in partic., of fishes,