nock noun. [nɒk] LME.
[Middle Dutch nocke (Dutch nok), whence also German Nock. Branch I may be a different word.]
I.
1. Archery. Orig., either of the small tips of horn fixed at each end of a bow and provided with a notch for holding the string; later, such a notch cut in this or in the bow itself. Also, a small piece of horn etc. fixed in the butt-end of an arrow, provided with a notch for receiving the bowstring; such a notch. LME.

2. The cleft in the buttocks. M16-E18.

[TahlilGaran] English Dictionary ▲

nock(1)
II. Nautical.

3. nockline, a part of a ship's rigging. Only in LME.

4. The tip or extremity of a yard-arm. Scot. Only in 16.

5. The foremost upper corner of some types of sail. L18.

[TahlilGaran] English Dictionary ▲

nock verb trans. [nɒk] LME.
[from the noun.]
1. Provide (a bow or arrow) with a nock or notch. Chiefly as nocked ppl adjective. LME.

2. Fit (an arrow) to a bowstring ready for shooting. LME.
nocking point the point of a bowstring to which the notch of an arrow is applied.

[TahlilGaran] English Dictionary ▲