pawl
/pɔ:l; pɔl/ n
1 lever with a catch that fits between the teeth (tooth 2) of a ratchet to prevent slipping or movement in a particular direction （防逆转的）棘爪, 掣爪.
2 (nautical 海) short bar used to prevent a capstan or windlass from recoiling （防止绞盘或起锚机逆转的）掣转杆.