have a moonflaw in the brain

have a moonflaw in the brain

To act very strangely. A "moonflaw" is an obsolete term to describe an odd trait or behavior seemingly influenced by the moon. The way she runs about in a frenzy when the sun goes down makes me wonder if she has a moonflaw in the brain.
See also: brain, have
Farlex Dictionary of Idioms.
See also:
  • inherit (something) from (someone)
  • inherit from
  • recognize (someone or something) by (something)
  • recognize by
  • adore
  • adore (one) for (something)
  • adore for doing
  • adore for having
  • that's (someone or something) for you
  • there's something for you