A measure of the tendency of a structure to return to its original form after removal of a deforming force. In medicine and physiology, usually a measure of the tendency of a hollow viscus (e.g., lung, urinary bladder, gallbladder) to recoil toward its original dimensions on removal of a distending or compressing force, the recoil pressure resulting from a unit distention or compression of the viscus; the reciprocal of compliance. The relationship between elasticity and elastance is of the same nature as that between the specific inductive capacity of an insulator material and the capacitance of a particular condenser made from that material.