Elasticity (physics)

A rubber band is elastic, and can be stretched

Economic elasticity is at elasticity (economics)

Something that is elastic can be stretched or deformed (changed) and returned to its original form, like a rubber band. It tries to come back to its first shape. The stress is the force applied; the strain is how much the shape is changed, and the elastic modulus is the ratio between those numbers.

This idea was first suggested by Robert Hooke in 1675.