Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
oppĭdātim, adv. [oppidum], by towns, in the towns, in every town (post-Aug.): ludos oppidatim constituerunt, Suet. Aug. 59: cum oppidatim victimae caederentur, id. Galb. 18.