1. [1930s+] homosexual.
2. [1950s+] of a person, crazy, eccentric.
3. [1990s+] of an object, crazy, unbelievable.
[1970s+] (orig. US) to drive mad, to infuriate.
[1970s] (US) to go suddenly insane, to lose control of one’s emotions.
1. to lose emotional control [image of an over-ripe banana that ‘goes soft’].
2. to delight in something absolutely; usu. as go bananas over.