bouncy

Bouncy is an adjective used to describe something that has the ability to bounce or rebound after contacting a surface. It is often used to characterize materials that are elastic or springy, as well as objects designed to rebound, such as balls, springs, and inflatable structures. In common usage, "bouncy" can also describe hair with a lively, springy texture or a person who is energetic in demeanor.

Physically, bounce results from elasticity—the tendency of a material to store and return kinetic energy during deformation. In physics, the extent of bounce is quantified by the coefficient of restitution, which ranges from 0 (no rebound) to 1 (perfectly elastic). Real-world bounces involve energy losses through heat, sound, and deformation of the contacting surfaces. The bounce height depends on material properties, mass, surface firmness, and gravity.

Common examples include rubber balls, trampolines, and "bouncy castles" or bounce houses, inflatable play structures widely used for children's recreation. In manufacturing, products may be marketed as "bouncy" to emphasize their resiliency and rebound characteristics.

Notes: "Bouncy" is informal; precise analysis uses descriptors such as elasticity, stiffness, and coefficient of restitution. The word's broad usage makes it a flexible descriptor across science, consumer products, and everyday language.