The Collaborative International Dictionary of English v.0.48:

Hearsay \Hear"say`\ (h[=e]r"s[=a]`), n.
   Report; rumor; fame; common talk; something heard from
   another.
   [1913 Webster]

         Much of the obloquy that has so long rested on the
         memory of our great national poet originated in
         frivolous hearsays of his life and conversation.
                                                  --Prof.
                                                  Wilson.
   [1913 Webster]

   Hearsay evidence (Law), that species of testimony which
      consists in a narration by one person of matters told him
      by another. It is, with a few exceptions, inadmissible as
      testimony. --Abbott.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hearsay
    adj 1: heard through another rather than directly; "hearsay
           information"
    n 1: gossip (usually a mixture of truth and untruth) passed
         around by word of mouth [syn: rumor, rumour, hearsay]

Moby Thesaurus II by Grady Ward, 1.0:

83 Moby Thesaurus words for "hearsay":
   absolute, adducible, admissible, attestative, attestive, authentic,
   based on, bruit, buzz, canard, certain, circumstantial,
   circumstantial evidence, collateral evidence, common talk,
   conclusive, convincing, corpus delicti, cry, cumulative,
   cumulative evidence, damning, decisive, determinative,
   direct evidence, documentary, documentary evidence, documented,
   evidence in chief, evidential, evidentiary, ex parte,
   ex parte evidence, extrinsic evidence, eye-witness, factual, final,
   firsthand, flying rumor, founded on, gossip, grapevine,
   grounded on, hearsay evidence, idea afloat, implicit,
   incontrovertible, incriminating evidence, indicative,
   indirect evidence, indisputable, intrinsic evidence, irrefutable,
   irresistible, latrine rumor, material, news stirring, nuncupative,
   on-dit, oral evidence, overwhelming, presumptive,
   presumptive evidence, prima facie evidence, probative, reliable,
   report, roorback, rumble, rumor, scuttlebutt, significant,
   suggestive, sure, symptomatic, talk, telling, town talk,
   unconfirmed report, valid, weighty, whisper,
   word-of-mouth evidence