Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
offĭcīnātor, ōris, m. [officina], one who keeps a workshop, a master-workman, an artificer, artist (post-Aug.), Vitr. 6, 11: noster, App. M. 9, p. 219, 28; Inscr. Orell. 1090: OFFICINATORES ET NVMMVLARI OFFICINARVM ARGENTARIARVM, ib. 3226: OFF. and OFFIC. MONETAE, ib. 3227.