sewellel
/sɪˈwɛləl
/noun
Another term for mountain beaver.The living rodent with the most archaic characters, most like the common ancestor of the Rodentia, is the sewellel or mountain beaver (which is not a true beaver at all) of the northwestern United States.
Origin
Early 19th century: from Chinook Jargon šwalál 'robe of mountain-beaver skin'.