I have heard people from Lima, Ohio refer to green peppers as mangoes. How did that come about?
I’d never heard of such a crazy thing in my life, but the map below shows why: I’ve never lived in the places where this occurs. The Dictionary of Regional American English (DARE) explains that this way:
There are more citations and examples given at the link above.
By the way, a bell pepper like the green ones you mention (Capsicum annuum) is called a capsicum in Antipodean English. They’re apparently quite generic about the whole business there.
It appears that:
green peppers "mangoes."