[nock] n [ME nocke notched tip on the end of a bow; akin to MD nocke summit] (14c) 1: one of the notches cut in either of two tips of horn fastened on the ends of a bow or in the bow itself for holding the string
2. a: the part of an arrow having a notch for the bowstring b: the notch itself
[2]nock vt (14c) 1: to make a nock in (a bow or arrow)
2: to fit (an arrow) against the bowstring