flexion
/ˈflekʃən/(亦作flection)
noun
mass noun
- the action of bending or the condition of being bent, especially the bending of a limb or joint（尤指四肢、关节）弯曲, 弯曲状态：
flexion of the fingers
手指的弯曲
count noun these protozoans can move by body flexions.这些原生动物可通过曲身移动。
词源
early 17th cent.: from Latin flexio（n-）, from flectere 'to bend'.