[1] : The Collaborative International Dictionary of English v.0.48

sedge \sedge\, n. oe. segge, as. secg; akin to lg. segge; --
   probably named from its bladelike appearance, and akin to l.
   secare to cut, e. saw a cutting instrument; cf. ir. seisg, w.
   hesg. cf. hassock, saw the instrument.
   1. bot. any plant of the genus carex, perennial,
      endogenous, innutritious herbs, often growing in dense
      tufts in marshy places. they have triangular jointless
      stems, a spiked inflorescence, and long grasslike leaves
      which are usually rough on the margins and midrib. there
      are several hundred species.
      1913 webster

   note: the name is sometimes given to any other plant of the
         order cyperaceae, which includes carex, cyperus,
         scirpus, and many other genera of rushlike plants.
         1913 webster

   2. zool. a flock of herons.
      1913 webster

   sedge hen zool., the clapper rail. see under 5th rail.
      

   sedge warbler zool., a small european singing bird
      acrocephalus phragmitis. it often builds its nest
      among reeds; -- called also sedge bird, sedge wren,
      night warbler, and scotch nightingale.
      1913 webster
see also:
hassock saw carex cyperaceae cyperus scirpus 
sedge hen rail sedge warbler acrocephalus phragmitis sedge bird 
sedge wren night warbler scotch nightingale 

[2] : WordNet (r) 2.0

sedge
     n : grasslike or rushlike plant growing in wet places having
         solid stems, narrow grasslike leaves and spikelets of
         inconspicuous flowers

Sedge >> S Words
Sedge, definition of term: Sedge
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