An Etymological Dictionary of the German Language, R (1891)
by Friedrich Kluge, translated by John Francis Davis
Rüpel
Friedrich Kluge2510811An Etymological Dictionary of the German Language, R — Rüpel1891John Francis Davis

Rüpel, m., ‘coarse fellow, lubber,’ prop. a Bav. abbreviation of Ruprecht (hence Rüpel and Rüppel as surnames); for a similar use of proper names comp. Metze. Probably the meaning of Rüpel was occasioned by Knecht Ruprecht, ‘Knight Robert’ (bugbear in nursery tales), in whose character maskers disported themselves in a rude and coarse manner.