Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
mullĕus calcĕus, or, absol., mul-lĕus, i, m. [mullus], a reddish or purplecolored shoe, worn only by the three highest magistrates (the consul, prætor, and curule ædile): mulleos genus calceorum aiunt esse; quibus reges Albanorum primi, deinde patricii sunt usi, quos putant a mullando dictos, i. e. suendo, Paul. ex Fest. p. 142 Müll.; Vop. Aurel. 49: nomen his (mullis) Fenestella a colore mulleorum calciamentorum datum putat, Plin. 9, 17, 30, § 65.