Having weak intellectual abilities or poor judgment; not intelligent or quick-thinking.
Compound of 'feeble' + 'brained' (having a brain of the specified kind). This word was used more commonly in the 1800s but is now considered outdated and potentially offensive.
Victorian writers loved calling characters 'feeblebrained,' but it's a perfect example of how older language could be really harsh—nowadays we've learned that intelligence varies and that mocking people for it is unkind.
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