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

bur \bur\, burr \burr\ b^ur, n. oe. burre burdock; cf. dan.
   borre, osw. borra, burdock, thistle; perh. akin to e. bristle
   burr- for burz-, or perh. to f. bourre hair, wool, stuff;
   also, according to cotgrave, "the downe, or hairie coat,
   wherewith divers herbes, fruits, and flowers, are covered,"
   fr. l. burrae trifles, ll. reburrus rough.
   1. bot. any rough or prickly envelope of the seeds of
      plants, whether a pericarp, a persistent calyx, or an
      involucre, as of the chestnut and burdock; a seed vessel
      having hooks or prickles. also, any weed which bears burs.
      1913 webster

            amongst rude burs and thistles.       --milton.
      1913 webster

            bur and brake and brier.              --tennyson.
      1913 webster

   2. the thin ridge left by a tool in cutting or shaping metal.
      see burr, n., 2.
      1913 webster

   3. a ring of iron on a lance or spear. see burr, n., 4.
      1913 webster

   4. the lobe of the ear. see burr, n., 5.
      1913 webster

   5. the sweetbread.
      1913 webster

   6. a clinker; a partially vitrified brick.
      1913 webster

   7. mech.
      a a small circular saw.
      b a triangular chisel.
      c a drill with a serrated head larger than the shank; --
          especially a small drill bit used by dentists.
          1913 webster

   8. cf. gael. borr, borra, a knob, bunch. zool. the round
      knob of an antler next to a deer's head. commonly written
      burr.
      1913 webster

   bur oak bot., a useful and ornamental species of oak
      quercus macrocarpa with ovoid acorns inclosed in deep
      cups imbricated with pointed scales. it grows in the
      middle and western united states, and its wood is tough,
      close-grained, and durable.

   bur reed bot., a plant of the genus sparganium, having
      long ribbonlike leaves.
      1913 webster
see also:
burr burr bur oak quercus macrocarpa bur reed sparganium 

[2] : WordNet (r) 2.0

bur
     n 1: seed vessel having hooks or prickles syn: burr
     2: small bit used in dentistry or surgery syn: burr
     v : remove the burrs from syn: burr
     also: burring, burred
see also:
burr burring burred 

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Bur, definition of term: Bur
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Bur Fish, definition of term: Bur Fish
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