Source : Webster's Revised Unabridged Dictionary (1913)

Rush \Rush\, n. [OE. rusche, rische, resche, AS. risce, akin to
   LG. rusk, risch, D. & G. rusch; all probably fr. L. ruscum
   butcher's broom; akin to Goth. raus reed, G. rohr.]
   1. (Bot.) A name given to many aquatic or marsh-growing
      endogenous plants with soft, slender stems, as the species
      of {Juncus} and {Scirpus}.

   Note: Some species are used in bottoming chairs and plaiting
         mats, and the pith is used in some places for wicks to
         lamps and rushlights.

   2. The merest trifle; a straw.

            John Bull's friendship is not worth a rush.
                                                  --Arbuthnot.

   {Bog rush}. See under {Bog}.

   {Club rush}, any rush of the genus {Scirpus}.

   {Flowering rush}. See under {Flowering}.

   {Nut rush}
      (a) Any plant of the genus {Scleria}, rushlike plants with
          hard nutlike fruits.
      (b) A name for several species of {Cyperus} having
          tuberous roots.

   {Rush broom}, an Australian leguminous plant ({Viminaria
      denudata}), having long, slender branches. Also, the
      Spanish broom. See under {Spanish}.

   {Rush candle}, See under {Candle}.

   {Rush grass}, any grass of the genus {Vilfa}, grasses with
      wiry stems and one-flowered spikelets.

   {Rush toad} (Zo["o]l.), the natterjack.

   {Scouring rush}. (Bot.) Same as {Dutch rush}, under {Dutch.}
      

   {Spike rush}, any rushlike plant of the genus {Eleocharis},
      in which the flowers grow in dense spikes.

   {Sweet rush}, a sweet-scented grass of Arabia, etc.
      ({Andropogon sch[oe]nanthus}), used in Oriental medical
      practice.

   {Wood rush}, any plant of the genus {Luzula}, which differs
      in some technical characters from {Juncus}.

Scour \Scour\ (skour), v. t. [imp. & p. p. {Scoured}; p. pr. &
   vb. n. {Scouring}.] [Akin to LG. sch["u]ren, D. schuren,
   schueren, G. scheuern, Dan. skure; Sw. skura; all possibly
   fr. LL. escurare, fr. L. ex + curare to take care. Cf.
   {Cure}.]
   1. To rub hard with something rough, as sand or Bristol
      brick, especially for the purpose of cleaning; to clean by
      friction; to make clean or bright; to cleanse from grease,
      dirt, etc., as articles of dress.

   2. To purge; as, to scour a horse.

   3. To remove by rubbing or cleansing; to sweep along or off;
      to carry away or remove, as by a current of water; --
      often with off or away.

            [I will] stain my favors in a bloody mask, Which,
            washed away, shall scour my shame with it. --Shak.

   4. [Perhaps a different word; cf. OF. escorre, escourre, It.
      scorrere, both fr. L. excurrere to run forth. Cf.
      {Excursion}.] To pass swiftly over; to brush along; to
      traverse or search thoroughly; as, to scour the coast.

            Not so when swift Camilla scours the plain. --Pope.

   {Scouring barrel}, a tumbling barrel. See under {Tumbling}.
      

   {Scouring cinder} (Metal.), a basic slag, which attacks the
      lining of a shaft furnace. --Raymond.

   {Scouring rush}. (Bot.) See {Dutch rush}, under {Dutch}.

   {Scouring stock} (Woolen Manuf.), a kind of fulling mill.

Source : WordNet®

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