English edit

Etymology edit

rattle +‎ brain

Noun edit

rattlebrain (plural rattlebrains)

  1. A rattlebrained person.
    • 1924, Herman Melville, chapter 13, in Billy Budd[1], London: Constable & Co.:
      a genial young fellow enough to look at, and something of a rattlebrain, to all appearance.
    • 1962, Isaac Bashevis Singer, translated by Isaac Bachevis Singer and Cecil Hemley, The Slave, New York: Farrar, Straus & Giroux, published 1985, Part III, p. 297:
      My mother, peace be with her, when she called me a rattlebrain, was right.