Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
plăcentārĭus, ĭi, m. [placenta], a pastry-cook, confectioner (late Lat.): inter urbana ministeria continentur … placentarii, Paul. Sent. 3, 6, 72; cf.: πλακουντάριος, placentarius, dulciarius, Gloss. Philox.