Friedrich Kluge2511860An Etymological Dictionary of the German Language, K — Knubbe1891John Francis Davis
Knubbe, Knuppe, m., ‘knot in wood,’ ModHG. only, from LG. knubbe, the cognates of which see under Knopf. We may also mention MidHG. knübel, to which Knuppe is related, as klauben to Kluppe.