Aspergill \As"per*gill\, Aspergillum \As`per*gil"lum\, n. [LL. aspergillum, fr. L. aspergere. See {Asperse}, v. t.] 1. The brush used in the Roman Catholic church for sprinkling holy water on the people. [Also written aspergillus.] [1913 Webster] 2. (Zool.) See {Wateringpot shell}. [1913 Webster]