screw in Wingdings is ⬧︎♍︎❒︎♏︎⬥︎

A straight line in space with which a definite linear magnitudetermed the pitch is associated (cf. 5th Pitch, 10 (b)). It is used toexpress the displacement of a rigid body, which may always be made toconsist of a rotation about an axis combined with a translationparallel to that axis.