The Collaborative International Dictionary of English v.0.48:

Sputter \Sput"ter\, v. t.
   To spit out hastily by quick, successive efforts, with a
   spluttering sound; to utter hastily and confusedly, without
   control over the organs of speech.
   [1913 Webster]

         In the midst of caresses, and without the least
         pretended incitement, to sputter out the basest
         accusations.                             --Swift.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sputter \Sput"ter\, n.
   Moist matter thrown out in small detached particles; also,
   confused and hasty speech.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sputter \Sput"ter\ (sp[u^]t"t[~e]r), v. i. [imp. & p. p.
   Sputtered (-t[~e]rd); p. pr. & vb. n. Sputtering.] [From
   the root of spout or spit to eject from the mouth. Cf.
   Splutter.]
   1. To spit, or to emit saliva from the mouth in small,
      scattered portions, as in rapid speaking.
      [1913 Webster]

   2. To utter words hastily and indistinctly; to speak so
      rapidly as to emit saliva.
      [1913 Webster]

            They could neither of them speak their rage, and so
            fell a sputtering at one another, like two roasting
            apples.                               --Congreve.
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   3. To throw out anything, as little jets of steam, with a
      noise like that made by one sputtering.
      [1913 Webster]

            Like the green wood . . . sputtering in the flame.
                                                  --Dryden.
      [1913 Webster]

WordNet (r) 3.0 (2006):

sputter
    n 1: the noise of something spattering or sputtering
         explosively; "he heard a spatter of gunfire" [syn:
         spatter, spattering, splatter, splattering,
         sputter, splutter, sputtering]
    2: an utterance (of words) with spitting sounds (as in rage)
       [syn: sputter, splutter]
    v 1: make an explosive sound; "sputtering engines"
    2: cause to undergo a process in which atoms are removed; "The
       solar wind protons must sputter away the surface atoms of the
       dust"
    3: climb awkwardly, as if by scrambling [syn: clamber,
       scramble, shin, shinny, skin, struggle, sputter]
    4: utter with a spitting sound, as if in a rage [syn: sputter,
       splutter]
    5: spit up in an explosive manner [syn: splutter, sputter,
       spit out]