Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
cistŭla, ae, f. dim. [cista], a little box, chest, or basket, Plaut. Am. 1, 1, 264; id. Rud. 2, 3, 58; 4, 4, 38 sq.; Mart. 4, 46, 13; App. M. 9, p. 236, 40.