Thanks for that, Q. I didn't quote from the OED, not because I'm lazy but because I don't have a copy.

Your first quote, "the londe of Rumbelowe", still does not exclude the meaning "rum". Perhaps a more extended quote might make this clearer one way or another. Your other indicating a carriage doesn't make sense in the context of the song. However your others, a blow or a loose woman, obviously could.

I assume you are not referring to me in your comment about others making up new meanings. I merely quoted a plausible derivation from a reference I happen to have.