An Etymological Dictionary of the German Language/Kaul-barsch

by Friedrich Kluge

Kaul-barsch, ‘round posterior,’ Kaul-kopf, ‘bull-head,’ Kaul-quappe, ‘ruff’; in these compounds Kaul signifies ‘a ball of small circumference’; MidHG. kûle, a variant of kugele (comp. steil from steigel); older ModHG. Kaule; comp. Keule.