A term used to describe a situation which is so utterly bizarre that it is both completely bananas and totally bonkers at the same time.
Dude, you texted me so many times my phone went banonkers!
They were eating babies and listening to Nickelback, it was so banonkers!
When something is bananas or bonkers, it's a mix of the two words. I was in the garden one day when I looked at one of the trees that i had recently pruned, in a matter of weeks it had doubled in size to my disbelief. I would usually say that this was 'bananas' or 'bonkers' but I got the two mixed up and out came 'banonkers' !!!!
Look at that flying pig....that's banonkers!!!