Lewis & Short

2. -do, -dāre (obsol., found only in the compounds, abdo, condo, abscondo, indo, etc.), 1, v. a. [Sanscr. root dhā-, da-dhāmi, set, put, place; Gr. θε-, τίθημι; Ger. thun, thue, that; Eng. do, deed, etc.]. This root is distinct from 1. do, Sanscr. , in most of the Arian langg.; cf. Pott. Etym. Forsch. 2, 484; Corss. Ausspr. 2, 410; but in Italy the two seem to have been confounded, at least in compounds, Curt. Gr. Etym. p. 254 sq.; cf. Max Müller, Science of Lang. Ser. 2, p. 220, N. Y. ed.; Fick, Vergl. Wört. p. 100.