What is the term for the part of a curve that is rounded?

The term that specifically describes the part of a curve that is rounded is "arc." An arc refers to a segment of a curve or a portion of the circumference of a circle. It captures the idea of a smooth, rounded section of a curve, distinguishing it from straight sections or other geometric components.

The other terms listed are related to the characteristics of curves and angles, but they do not specifically describe a rounded part. Slope typically refers to the steepness of a line rather than a rounded section. An angle is formed by two rays or lines originating from a common point and does not apply directly to curves. While "curve" is a broader term that includes all types of curved lines, it does not specifically denote the rounded portion alone. Thus, "arc" is the most accurate term to describe a rounded part of a curve.