Idiom: To go bananas
Meaning: (1) to go or act a little crazy; (2) to become very angry or lose control of your temper.
Context #1 – A man is complaining that his best friend painted a mural on his backyard wall without asking him.
George: Hey Ted, you didn’t have to go bananas on me just because I drew a mural on your backyard wall.
Ted: George, your little art work cost me two thousand dollars. I think I can go a little bananas.
George: But it was a picture of you and me together. You’re my best friend.
Ted: The only one that went bananas here is you. It’s easier to print a picture or poster out. You went to buy paint and spent hours working on that.
Context #2 –
Dominic: I may have gone bananas this past weekend.
Brian: Why do you say that? It’s not unusual for you to do crazy things.
Dominic: I spend forty thousand dollars on getting parts for my car.
Brian: Wow! I may go bananas just from hearing what you did.
Meaning: To go bananas means to go a little crazy/wild or to lose one’s temper. It’s not always a negative meaning. It could be used as an expression of exaggeration. For example, in context 2 Dominic and Brian aren’t having a negative conversation, they’re just both surprised at the actions taken by Dominic. In context #1, George expresses to Ted that he didn’t have to become too upset about his gift, while Ted explains to George that his actions were, in his opinion, crazy.