The Collaborative International Dictionary of English v.0.48:

Babble \Bab"ble\ (b[a^]b"b'l), v. i. [imp. & p. p. Babbled
   (b[a^]b"b'ld); p. pr. & vb. n. Babbling.] [Cf. LG. babbeln,
   D. babbelen, G. bappeln, bappern, F. babiller, It. babbolare;
   prob. orig., to keep saying ba, imitative of a child learning
   to talk.]
   1. To utter words indistinctly or unintelligibly; to utter
      inarticulate sounds; as a child babbles.
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   2. To talk incoherently; to utter unmeaning words.
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   3. To talk much; to chatter; to prate.
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   4. To make a continuous murmuring noise, as shallow water
      running over stones.
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            In every babbling brook he finds a friend.
                                                  --Wordsworth.
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   Note: Hounds are said to babble, or to be babbling, when they
         are too noisy after having found a good scent.
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   Syn: To prate; prattle; chatter; gossip.
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