scatterbrain

from WordNet (r) 3.0 (2006)

scatterbrain
    n 1: a flighty and disorganized person [syn: {scatterbrain},
         {forgetful person}]

from The Collaborative International Dictionary of English v.0.48

Scatter-brain \Scat"ter-brain`\, n.
   A giddy or thoughtless person; one incapable of concentration
   or attention. [Written also {scatter-brains}.]
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

18 Moby Thesaurus words for "scatterbrain":
      birdbrain, featherbrain, featherhead, flibbertigibbet, fool,
      giddybrain, giddyhead, goose, harebrain, rattlebrain, rattlehead,
      rattlepate, scatterbrains, shallowbrain, shallowpate, shatterbrain,
      silly, simpleton

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