Rattlebrain is a related term of dimwit.
As nouns the difference between rattlebrain and dimwit
is that rattlebrain is a rattlebrained person while dimwit is (pejorative) a person who is deficient in intelligence.
dimwit
English
Noun
(
en noun)
(pejorative) A person who is deficient in intelligence.
Synonyms
* See
Derived terms
* dimwitted
* dimwittedly
* dimwittedness
See also
* halfwit
* nitwit