rat·​tle·​brain ˈra-tᵊl-ˌbrān How to pronounce rattlebrain (audio)
: a flighty or thoughtless person
rattlebrained adjective

Examples of rattlebrain in a Sentence

in a medical situation of this seriousness we don't need some rattlebrain running around in a panic

Word History

First Known Use

1704, in the meaning defined above

Time Traveler
The first known use of rattlebrain was in 1704

Dictionary Entries Near rattlebrain

Cite this Entry

“Rattlebrain.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rattlebrain. Accessed 29 Sep. 2023.

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