[f. STRAIGHTEN v. + -ER1.] One who or something that straightens.
1611. Cotgr., Dresseur, a straightener, directer, leueller.
1832. Ht. Martineau, Hill & Valley, iv. (1833), 61. They saw … the straighteners who straighten the bars when they are hot, and mark them with the stamp of the works where they are made.
1875. Knight, Dict. Mech., 2414/2. Fig. 5940 is a railway-rail straightener.
