1721. Bailey, To Knub, Knuble, to beat with the Fist or Knuckles.
1783. Morell, Ainsworths Lat. Dict., I. To knubble, Pugnis contundĕre.
a. 1825. Forby, Voc. E. Anglia, Knubble, to handle clumsily; using thumbs and knuckles, as in kneading dough.
1828. Webster, Knub, knubble, to beat; to strike with the knuckle. [Not used.]