Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
subter-dūco, xi, 3, v. a., to carry off secretly, to steal away any thing (Plautin.): ne tibi clam se subterducat istinc, Plaut. Mil. 2, 3, 72: si huic occasioni tempus sese subterduxerit, id. As. 2, 2, 12.