Green’s Dictionary of Slang

stammer and stutter n.

butter.

1960		J. Franklyn Dict. of Rhy. Sl.
1969		S.T. Kendall Up the Frog.
1971		J. Jones Rhy. Cockney Sl.
1992		R. Puxley Cockney Rabbit.
2002		B. Kirkpatrick Wicked Cockney Rhy. Sl.