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Back with the buffalo nickel, on the front of the money it had a head, and on the back it had a buffalo with a tail. It's an American-coined term.
Per Dictionary.com, the term can be traced at...
A Dog While some people in the last week of November 2010 started a meme that attempted to name the male otter "Meowter" it's really just a tumblr meme and not a real taxonomic name for a male otter.