torsion
tor.sion \'to.r-sh*n\ \'to.r-shn*l, -sh*n-*l\ \-e-\ n [LL torsus, pp. of L torque-re to twist] 1: the twisting or wrenching of a body by the exertion of forces tending to turn one end or part about a longitudinal axis while the other is held fast or turned in the opposite direction; also : the state of being twisted 2: the reactive torque that an elastic solid exerts by reason of being unde r torsion - tor.sion.al aj