What is of or pertaining to torsion; resulting from torsion, or the force with which a thread or wire returns to a state of rest after having been twisted round its axis; as, torsional force called?

torsional — Of or pertaining to torsion; resulting from torsion, or the force with which a thread or wire returns to a state of rest after having been twisted round its axis; as, torsional force. (Webster's 1913.)

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