Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
sĭtella, ae, f. dim. [situla], a kind of urn used in drawing lots. It was made narrow at the top, so that but one lot at a time could be on the surface of the water with which it was partly filled, Plaut. Cas. 2, 4, 17; 2, 5, 34; 2, 5, 43; 2, 6, 11; 2, 6, 44: sitellam detulit, Auct. Her. 1, 12, 21: de M. Octavio deferre sitellam, Cic. N. D. 1, 38, 106: sitella lata est, ut sortirentur, Liv. 25, 3, 16 Weissenb. ad loc.; 41, 18, 8.