Lewis Short
dē-sub
* Praep. c. abl., below, beneath (late Lat.; cf. desuper): desub Alpibus, id est, desub ipsis Italiae faucibus,Flor. 2, 3, 2: desub oculo,Veg. Vet. 2, 19: desub rivo, Innocent. de Cas. liter. p. 226 ed. Goes.: desub se,id. ib. 223: lucernam desub modio ejecit,Fulg. Mythol. 3, 6.
Charlton T. Lewis, Charles Short, A Latin Dictionary