external tooth lock washer
/ɛkstˈɜːnəl ˈtuːθ ˈlɒk ˈwɒʃə/
n
中文：外齿锁紧垫圈
中文 · 外齿锁紧垫圈Español · arandela de presión de dientes externosFrançais · rondelle à denture extérieure
Meaning：Washer having protuberances on the outside so that a screw tightens securely and will not loosen.