形变 is a technical term meaning 'deformation' or 'transform' depending on the field. In physics and materials science, it refers to the change in shape of an object under stress (e.g., 弹性形变 'elastic deformation'). In linguistics, it describes a morphological or phonological transformation (e.g., 音位形变 'phonemic transformation'). The two senses are domain-specific, so context determines which one applies.