Peppergrass

Pep"per*grass` (?), n. (Bot.) (a) Any herb of the cruciferous genus Lepidium, especially the garden peppergrass, or garden cress, Lepidium sativum; -- called also pepperwort. All the species have a pungent flavor. (b) The common pillwort of Europe (Pilularia globulifera). See Pillwort.