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.
1. To spit, or to emit saliva from the mouth in small,
scattered portions, as in rapid speaking.
2. To utter words hastily and indistinctly; to speak so
rapidly as to emit saliva.
They could neither of them speak their rage, and so
fell a sputtering at one another, like two roasting
3. To throw out anything, as little jets of steam, with a
noise like that made by one sputtering.
Like the green wood . . . sputtering in the flame.