手筋

flexor tendon (coll.) / tesuji (a skillful move in the game of Go) (orthographic borrowing from Japanese 手筋 "tesuji")

hand / (formal) to hold / person engaged in certain types of work / person skilled in certain types of work / personal(ly) / convenient / classifier for skill / CL:雙|双[shuang1],隻|只[zhi1]

muscle / tendon / veins visible under the skin / sth resembling tendons or veins (e.g. fiber in a vegetable)