Source : Webster's Revised Unabridged Dictionary (1913)

Rud \Rud\, n. [AS. rudu, akin to re['a]d red. [root]113. See
   {Red}, and cf. {Ruddy}.]
   1. Redness; blush. [Obs.]

   2. Ruddle; red ocher.

   3. (Zo["o]l.) The rudd.

Rud \Rud\, v. t.
   To make red. [Obs.] --Spenser.