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

blabbermouth \blabbermouth\ n.
   someone who gossips indiscreetly.

   syn: blabber, tattletale, taleteller, talebearer, telltale.
        wordnet 1.5

[2] : WordNet (r) 2.0

blabbermouth
     n : someone who gossips indiscreetly syn: tattletale, tattler,
          taleteller, talebearer, telltale
see also:
tattletale tattler taleteller talebearer telltale 

[3] : Moby Thesaurus II by Grady Ward, 1.0

28 moby thesaurus words for "blabbermouth":
   babbler, betrayer, blab, blabber, blabberer, chatterer, delator,
   fink, gabber, gossip, informer, jabberer, magpie, narc, peacher,
   prater, prattler, snitch, snitcher, spy, squealer, stool pigeon,
   stoolie, talebearer, tattler, tattletale, telltale,
   whistle-blower

Blabbermouth >> B Words
Blabbermouth, definition of term: Blabbermouth
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