torsion

Imagine wringing out a wet cloth or turning a screwdriver. That twisting action is torsion. It is the force or stress that makes something twist around its center line. You often meet it in metal rods, bolts, springs, and other parts that are being turned. The word can also describe the twisted state itself, especially in technical or medical contexts.

Torsion is a twisting force applied to an object, or the stress produced when something is twisted around its axis. It is different from bending: bending curves an object, while torsion twists it. Think of a towel being wrung out, a key turning in a lock, or a car shaft carrying turning force from one part to another.

This idea is important in engineering and physics. Engineers must account for torsion when designing drive shafts, springs, screws, tools, and other parts that must handle twisting without breaking. A metal bar under this kind of load experiences torsional stress, which is the internal stress caused by the twist.

The word also appears in medicine. There, it can mean that a body part has twisted abnormally, cutting off blood flow or causing serious pain, as in ovarian torsion or testicular torsion. In this sense, the focus is not on machinery but on a dangerous physical twisting inside the body.

So, whether you are talking about a spring, a shaft, or a medical emergency caused by twisting, torsion is about rotation, twisting force, and the strain or condition that comes from that twist.