full of beans

full of beans idiom
  1. Lively, energetic, in high spirits, as in The children were full of beans today, looking forward to their field trip. This expression has no valid explanation. [c. 1840]
  2. Also, full of prunes. Acting foolish, talking nonsense, as in One cup of coffee won't hurt you—you're full of prunes. [c. 1930] Also see full of crap.

The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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