knuckling

n.

突球；

v.

（指人）指关节( knuckle的现在分词 )；（指动物）膝关节，踝；

steering knuckle转向关节

knuckle down屈服；开始认真工作

near the knuckle[口语](笑话等)近乎猥亵的，近乎下流的，近乎粗鄙的

knuckle sandwich对准嘴的一拳

knuckling:
A Study of Knuckling Effect of Soccer Ball (P106)
A Study of Knuckling Effect of Soccer Ball (P106)
Flow structure of knuckling effect in footballs
Aerodynamics of knuckling effect shot using kick-robot
Ball impact dynamics of knuckling shot in soccer
Knuckling Under? School Superintendents and Accountability-Based Educational Reform.
Analysis of the swing motion on knuckling shot in soccer
Idiopathic peripheral neuropathy in a horse with knuckling.
Cable termination assembly, nipping and knuckling machine, and method