Source : Webster's Revised Unabridged Dictionary (1913)

Jabber \Jab"ber\, v. i. [imp. & p. p. {Jabbered}; p. pr. & vb.
   n. {Jabbering}.] [Cf. {Gibber}, {Gabble}.]
   To talk rapidly, indistinctly, or unintelligibly; to utter
   gibberish or nonsense; to chatter. --Swift.