The Collaborative International Dictionary of English v.0.48:

Rumor \Ru"mor\, n. [F. rumeur, L. rumor; cf. rumificare,
   rumitare to rumor, Skr. ru to cry.] [Written also rumour.]
   1. A flying or popular report; the common talk; hence, public
      fame; notoriety.
      [1913 Webster]

            This rumor of him went forth throughout all Judea,
            and throughout all the region round about. --Luke
                                                  vii. 17.
      [1913 Webster]

            Great is the rumor of this dreadful knight. --Shak.
      [1913 Webster]

   2. A current story passing from one person to another,
      without any known authority for its truth; -- in this
      sense often personified.
      [1913 Webster]

            Rumor next, and Chance,
            And Tumult, and Confusion, all embroiled. --Milton.
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   3. A prolonged, indistinct noise. [Obs.] --Shak.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Rumor \Ru"mor\, v. t. [imp. & p. p. Rumored; p. pr. & vb. n.
   Rumoring.]
   To report by rumor; to tell.
   [1913 Webster]

         'T was rumored
         My father 'scaped from out the citadel.  --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

rumor
    n 1: gossip (usually a mixture of truth and untruth) passed
         around by word of mouth [syn: rumor, rumour, hearsay]
    v 1: tell or spread rumors; "It was rumored that the next
         president would be a woman" [syn: rumor, rumour,
         bruit]

Moby Thesaurus II by Grady Ward, 1.0:

60 Moby Thesaurus words for "rumor":
   announce, blab, break the news, breathe, bring word, bruit,
   bruit about, buzz, canard, chat, circulate, common talk, cry,
   flying rumor, give a report, give tidings of, gossip, grapevine,
   hearsay, idea afloat, info, inform, information, intimate,
   latrine rumor, leak, low-down, make known, mumble, mutter, news,
   news stirring, noise abroad, on dit, on-dit, pass around, poop,
   put about, rehearse, relate, report, reveal, roorback, rumble,
   rumor, say, scoop, scuttlebutt, suggest, susurration, talk, tattle,
   tell, tidings, tittle-tattle, town talk, unconfirmed report,
   undertone, whisper, write up



Bouvier's Law Dictionary, Revised 6th Ed (1856):

RUMOR. A general public report of certain things, without any certainty as
to their truth.
     2. In general, rumor cannot be received in evidence, but when the
question is whether such rumor existed, and not its truth or falsehood, then
evidence of it may be given.



The Devil's Dictionary (1881-1906):

RUMOR, n.  A favorite weapon of the assassins of character.

    Sharp, irresistible by mail or shield,
        By guard unparried as by flight unstayed,
    O serviceable Rumor, let me wield
        Against my enemy no other blade.
    His be the terror of a foe unseen,
        His the inutile hand upon the hilt,
    And mine the deadly tongue, long, slender, keen,
        Hinting a rumor of some ancient guilt.
    So shall I slay the wretch without a blow,
    Spare me to celebrate his overthrow,
    And nurse my valor for another foe.
                                                           Joel Buxter