1344, from M.E. raggi "ragged" + fanciful ending (or else second element is M.Du. muffe "mitten"). Ragged was used of the devil from c.1300 in ref. to "shaggy" appearance. Used by Langland as the name of a demon (cf. O.Fr. Ragamoffyn, name of a demon in a mystery play); sense of "dirty, disreputable boy" is from 1581.