Yes, plantain is a kind of super-banana that grows in South America. I have no explanation why a common yard plant in North America is given the same name, but there it is. There are two types of plantain common in North America, and someday I shall find their proper names and put them in here. For now, I have pictures!
One type has a rounded leaf, similar in shape to a baby spinach leaf. The other has a longer, skinnier leaf. The main distinctive about plantain leaves is that their veins are parallel, rather than branching off in many directions.
While the two types of plantain seem to be equally effective, I find that I prefer to use the rounder variety. The skinny variety seems more “veiny” and is harder to chew.