Oxford Advanced American Dictionary

Definition of banana noun from the Oxford Advanced Learner's Dictionary

banana

noun
banana pronunciation English bəˈnɑːnə banana pronunciation American bəˈnænə
 
a long curved fruit with a thick yellow skin and soft flesh, that grows on trees in hot countries
a bunch of bananas
Idioms

go bananas

(slang) to become angry, crazy or sillyHe lost his job and just went bananas.The British press has gone bananas, proclaiming the end of civilization as we know it.