Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
mātercŭla, ae, f. dim. [mater], a little mother (class.): tune igitur mea matercula? Plaut. Fragm. ap. Prisc. p. 601 P.: materculae suae festivus filius, * Cic. Fl. 36, 91; Hor. Ep. 1, 7, 7.