mandrel /ˈmæn.dɹəl/noun 2verb 1forms 5 noun2 •A round object used as an aid for shaping a material, e.g. shaping or enlarging a ring, or bending or enlarging a pipe without creasing or kinking it.The coil springs were manufactured by winding the heated steel strip direct out of the furnace on to a mandrel of the requisite size. — 1945 •A tool or component of a tool that guides, grips or clamps something, such as a workpiece to be machined, a machining tool or a part while it is moved.This socket forms the starting point of the piercing operation, enabling the mandrel to center itself on the work. — 1920 verb1 •To shape with a mandrel. formsmandreled · mandrelled · mandreling · mandrelling · mandrels