Source : Webster's Revised Unabridged Dictionary (1913)

Nock \Nock\, n. [See {Notch}.]
   1. A notch.

            He took his arrow by the nock.        --Chapman.

   2. (Naut.) The upper fore corner of a boom sail or of a
      trysail.

Nock \Nock\, v. t.
   To notch; to fit to the string, as an arrow; to string, as a
   bow. --Chapman.

Source : WordNet®

nock
     v : make small marks into the surface of; "score the clay before
         firing it" [syn: {score}, {mark}]