The Collaborative International Dictionary of English v.0.48:

Rabble \Rab"ble\, a.
   Of or pertaining to a rabble; like, or suited to, a rabble;
   disorderly; vulgar. [R.] --Dryden.
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The Collaborative International Dictionary of English v.0.48:

Rabble \Rab"ble\, v. t. [imp. & p. p. Rabbled (r[a^]b"b'ld);
   p. pr. & vb. n. Rabbling (r[a^]b"bl[i^]ng).]
   1. To insult, or assault, by a mob; to mob; as, to rabble a
      curate. --Macaulay.
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            The bishops' carriages were stopped and the prelates
            themselves rabbled on their way to the house. --J.
                                                  R. Green.
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   2. To utter glibly and incoherently; to mouth without
      intelligence. [Obs. or Scot.] --Foxe.
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   3. To rumple; to crumple. [Scot.]
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The Collaborative International Dictionary of English v.0.48:

Rabble \Rab"ble\ (r[a^]b"b'l), n. [Etymol. uncertain.] (Iron
   Manuf.)
   An iron bar, with the end bent, used in stirring or skimming
   molten iron in the process of puddling.
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The Collaborative International Dictionary of English v.0.48:

Rabble \Rab"ble\, v. t.
   To stir or skim with a rabble, as molten iron.
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The Collaborative International Dictionary of English v.0.48:

Rabble \Rab"ble\, v. i. [Akin to D. rabbelen, Prov. G. rabbeln,
   to prattle, to chatter: cf. L. rabula a brawling advocate, a
   pettifogger, fr. rabere to rave. Cf. Rage.]
   To speak in a confused manner. [Prov. Eng. & Scot.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Rabble \Rab"ble\, n. [Probably named from the noise made by it
   (see Rabble, v. i.) cf. D. rapalje rabble, OF. & Prov. F.
   rapaille.]
   1. A tumultuous crowd of vulgar, noisy people; a mob; a
      confused, disorderly throng.
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            I saw, I say, come out of London, even unto the
            presence of the prince, a great rabble of mean and
            light persons.                        --Ascham.
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            Jupiter, Mercury, Bacchus, Venus, Mars, and the
            whole rabble of licentious deities.   --Bp.
                                                  Warburton.
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   2. A confused, incoherent discourse; a medley of voices; a
      chatter.
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   The rabble, the lowest class of people, without reference
      to an assembly; the dregs of the people. "The rabble call
      him `lord.'" --Shak.
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WordNet (r) 3.0 (2006):

rabble
    n 1: a disorderly crowd of people [syn: mob, rabble, rout]
    2: disparaging terms for the common people [syn: rabble,
       riffraff, ragtag, ragtag and bobtail]

Moby Thesaurus II by Grady Ward, 1.0:

60 Moby Thesaurus words for "rabble":
   and bobtail, army, bourgeoisie, canaille, cluster, cohue,
   common ruck, commonalty, commoners, crowd, crush, deluge, dregs,
   dregs of society, flock, flood, galaxy, gang, heap, hoi polloi,
   horde, host, jam, legion, lower classes, many, mass, masses, mob,
   mod, multitude, other half, outcasts, panoply, peasantry, people,
   polloi, populace, press, proletariat, public, rabblement, raff,
   rag, ragtag, ragtag and bobtail, rank and file, riffraff, rout,
   ruck, scum, scurf, spate, swarm, tag, the great unwashed, throng,
   trash, unwashed, vermin



The Devil's Dictionary (1881-1906):

RABBLE, n.  In a republic, those who exercise a supreme authority
tempered by fraudulent elections.  The rabble is like the sacred
Simurgh, of Arabian fable -- omnipotent on condition that it do
nothing.  (The word is Aristocratese, and has no exact equivalent in
our tongue, but means, as nearly as may be, "soaring swine.")