We know, everybody is deformed or strained when a force is applied on it, but it returns to its original shape and size as soon as the force is withdrawn. But there is a limit of the applied force, above which the body does not return to its original shape and size. The body becomes permanently deformed i.e., it becomes plastic. So elastic limit is defined in the following way:
Elastic limit is the maximum value of the applied force upto which the body remains perfectly elastic and when the limit is exceeded the material of the body shows plastic behaviour. This limit is different for different materials. It means the maximum extent to which a solid may be stretched without permanent alteration of size or shape. Steel and diamond have very high elastic limit, whereas zinc has low elastic limit.