"Concavity" Natural Recordings by Native Speakers
Concavity refers to a curved or bent shape that is inward, opposite of convexity. It is a property of a shape or a surface where it curves or bends inward, often forming a depression or a hollow. This term is commonly used in mathematics, physics, and engineering to describe the shape of a curve or a surface. For example, a sphere has a concave curvature when viewed from the outside, while a saddle-shaped surface has a concave curvature in two directions.