|Enhanced with a bite from Hungry Sam!|
"What are plantains?" a person might ask. "This is a plantain," I reply:
"Isn't that just a banana?" that same person might also ask. "NO DAMMIT," I calmly reply. Then I check Wikipedia, and see that a plantain is, in fact a banana. There is no "botanical distinction" between a banana and a plaintain; the former is smaller and sweeter due to specific environmental factors and not to a difference in genetics. The terms, then, are tied to more to usage than anything else -- a "plaintain" is a cooking banana.