Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
pĕcūnĭāris, e, adj. [pecunia], of or belonging to money, pecuniary (post-class. and rare for pecuniarius): damnatio, i. e. to pay a fine, Dig. 48, 19, 10 fin. dub. (al. pecuniaria).
Hence, adv.: pĕcūnĭārĭter, relating to money, pecuniarily, Dig. 47, 1, 3.