radius of curvatureEnglishOxford New American Dictionaryradius of curvature /ˈrādēəs əv, , ˈreɪdiəs əv, ə ˈkərvəCHər, ə ˈkərvətʃər/ ▸ noun Mathematics the radius of a circle which touches a curve at a given point and has the same tangent and curvature at that point.