Entry 2 senses Webster, 1913 Deformation /dēfˌ-ôr-māsh'-ən/ · Def·or·ma·tion · IPA /ˌdɛfɚˈmeɪʃn̩/ 01 n. The act of deforming, or state of anything deformed. 1. The act of deforming, or state of anything deformed. 2. Transformation; change of shape.