reedmace

from WordNet (r) 3.0 (2006)

reedmace
    n 1: tall marsh plant with cylindrical seed heads that explode
         when mature shedding large quantities of down; its long
         flat leaves are used for making mats and chair seats; of
         North America, Europe, Asia and North Africa [syn:
         {cat's-tail}, {bullrush}, {bulrush}, {nailrod}, {reed
         mace}, {reedmace}, {Typha latifolia}]

from The Collaborative International Dictionary of English v.0.48

Reed-mace \Reed"-mace`\ (r[=e]d"m[=a]s`), n. (Bot.)
   The cat-tail.
   [1913 Webster]