Word Origin & History
shenanigan1855, of uncertain origin. Earliest records of it are in San Francisco and Sacramento, California, U.S. Suggestions include Sp. chanada, a shortened form of charranada "trick, deceit;" or, less likely, Ger. Schenigelei, peddler's argot for "work, craft," or the related Ger. slang verb schinäglen.
Another guess centers on Ir. sionnach "fox."