Some solid bodies have a tendency to maintain their shape, and when deformed by an external force, they return to their original shape as soon as the force is removed. This property is known as elasticity.
某些固体物质有一种保持原状的特性，在外力的作用下其形状发生变化，一旦外力小时，就立即恢复原状，这种特性被称为弹性。