The Collaborative International Dictionary of English v.0.48:

Bonnyclabber \Bon"ny*clab`ber\ (-kl[a^]b`b[~e]r), n. [Ir.
   bainne, baine, milk + clabar mud, mire.]
   Coagulated sour milk; loppered milk; curdled milk; --
   sometimes called simply clabber. --B. Jonson.
   [1913 Webster]