- crazy or eccentric
- wildly enthusiastic, excited, etc.
See bananas in American Heritage Dictionary 4
Crazy: “That's the horrible thing when you're bananas—nobody can know the awful things that are going on in your head” (Otto Friedrich). “City dwellers . . . are subjected to so much noise it drives them bananas” (New Yorker).
Origin: From banana, worthless or crazy person
Origin: , from banana
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