[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. 弯手指。 [count noun]these protozoans can move by body flexions. 这些原生动物可通过曲身移动。
语源
early 17th cent.: from Latin flexio(n-), from flectere 'to bend'