sycophantiose

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.

sȳcŏphantĭōsē (sūc-), adv. [sycophanta],

craftily , knavishly , deceitfully : agere quicquam (with malefice), Plaut. Ps. 4, 7, 113.