Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
stătĭōnārĭus, a, um, adj. [statio, II.], of or belonging to a post or station (jurid. Lat.): stationarii milites, soldiers stationed at a post, a kind of gendarmery instituted by Augustus for suppressing the grassatores, Suet. Aug. 32; Dig. 11, 4, 1; 11, 4, 4; 1, 12, 1 fin.
As subst.: stătĭōnārĭus, i, m.