Where does “bok” come from?

I can't write this etymology because the chain provided contains only circular repetitions (bunker, mate, bunker, mate, bunker, mate, bunker) with no actual origin information, and the headword "bok" doesn't appear in the chain at all. A valid etymology requires a clear language progression to an ultimate source with at least some attestable meaning.

bok (English): keen or willing; The clucking sound of a chicken

Definitions

  1. keen or willing; The clucking sound of a chicken

Ancestry of “bok”, step by step

bok traces back through 3 separate lines of ancestry.

via Afrikaans bok

StepLanguageWordMeaning
1Afrikaansbokgoat; antelope, buck; lover
2Dutchbokmale goat, buck, billy; vaulting horse; a crane...
3Middle Dutchbocbuck, male goat
4Old Dutchbūcbuck, male goat
5Proto-West Germanicbukkbuck, male goat
6Proto-Germanic*bukkaz
7Proto-Indo-Europeanbʰuǵ-buck, he-goat
8Proto-North CaucasianbVχc̣V
9Proto-North CaucasianbVc̣Vyoung he-goat

via German Bock

StepLanguageWordMeaning
1GermanBockhe-goat; buck; apparatus used for performing...
2Romanibokhhunger
3Sauraseni Prakrit????????hunger, wish to eat
4Sanskritबुभुक्षाdesire of enjoying anything; wish to eat,...
5Sanskritबुभुक्षतिwishes to eat
6Proto-Indo-Europeanbʰewg-to flee; to enjoy, benefit

via Swedish bok

StepLanguageWordMeaning
1Swedishbokbook; beech
2Old Swedishbōkbook
3Old Norsebókbeech; textile fabric with figures woven in it;...
4Proto-Germanicbōksletter, written message, inscriptions carved into...
5Proto-Indo-Europeanbʰeh₂ǵosbeech

Words derived from “bok

Every word from Proto-North Caucasian bVc̣V