Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
formella, ae, f. dim. [forma], a little form or mould for baking in (late Lat.): in formella piscem formare, Apic. 9, 13; or for moulding cheese: casei, Vulg. 1 Reg. 17, 18.