The Collaborative International Dictionary of English v.0.48:

Splutter \Splut"ter\ (spl[u^]t"t[~e]r), v. i. [imp. & p. p.
   Spluttered (-t[~e]rd); p. pr. & vb. n. Spluttering.]
   [Prov. E. splutter, eqivalent to sputter. Cf. Sputter.]
   To speak hastily and confusedly; to sputter. [Colloq.]
   --Carleton.
   [1913 Webster]