WordNet (r) 3.0 (2006):

Equisetum hyemale robustum
    n 1: evergreen erect horsetail with rough-edged stems; formerly
         used for scouring utensils [syn: scouring rush, rough
         horsetail, Equisetum hyemale, Equisetum hyemale
         robustum, Equisetum robustum]