rattlebrain(redirected from rattle brain)
A stupid or foolish person, especially one whose thoughts are disjointed or chaotically disorganized. Sometimes hyphenated. These were not the unpredictable acts of some rattlebrain—they were coldly calculated. I don't know how they could let a rattle-brain like her lead this company.
n. a stupid person. Please try not to be such a rattlebrain! Pay attention to what you are doing.