Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. marcŭlus or martŭlus, i, m. dim. [marcus], a small hammer, a hammer (ante-class. and post-Aug.): malleus vocatur, quia dum quid calet et molle est, caedit et producit: marcus, malleus major: et dictus marcus, quod major sit ad caedendum, et fortior: marcellus mediocris: marculus malleus pusillus, Isid. Orig. 19, 7, 2; Lucil. ib.: tegulas invenit Cinyra, et metalla aeris, item forcipem, martulum, vectem, incudem, Plin. 7, 56, 57, § 195: alii caelo et marculo gemmulas exsculpunt, Front. ad Caes. 4, 4, 3 Mai.: aerariorum marculi, Mart. 12, 57, 6.