c. 1400, deformen, difformen, "to disfigure, mar the natural form or shape of," from Old French deformer (13c.) and directly from Latin deformare "put out of shape, disfigure," from de (see de-) + formare "to shape, fashion, build," also figurative, from forma "form, contour, figure, shape" (see form (n.)). Related: Deformed; deforming.
