pawl
/pɔːl/noun
1- a pivoted curved bar or lever whose free end engages with the teeth of a cogwheel or ratchet so that the wheel or ratchet can only turn or move one way（防逆转的）棘爪, 推爪。
1.1
- each of a set of short stout bars that engage with the whelps and prevent a capstan, windlass, or winch from recoiling（防止绞盘或起锚机逆转的）掣转杆。
词源
early 17th cent.: perhaps from Low German and Dutch pal （related to pal 'fixed'）.