【Elastic】 ,  【resilient】 ,  【springy】 ,  【flexible】 ,  【supple】  are comparable when they mean able to endure strain (as extension, compression, twisting, or bending) without being permanently affected or injured.

【Elastic】  and  【resilient】  are both general and scientific terms; the scientific senses are later and are in part derived from the earlier meanings.

【Elastic】 in nontechnical use is applied chiefly to substances or materials that are easy to stretch or expand and that quickly recover their shape or size when the pressure is removed.

In scientific use  【elastic】  is applicable to a solid that may be changed in volume or shape, or to a fluid (gas or liquid) that may be changed in volume, when in the course of the deformation of such a solid or fluid forces come into play which tend to make it recover its original volume or shape once the deforming force or forces are removed.

The term in such use describes a property (elasticity ) which a substance possesses up to the point (the  【elastic】 limit ) beyond which it cannot be deformed without permanent injury.

【Resilient】  in nontechnical use is applicable to whatever springs back into place or into shape especially after compression; thus, rising bread dough is said to be  【resilient】  because it quickly recovers from a deforming pressure by the hand; a tree’s branch may be described as  【resilient】  when it snaps back into its former position once a pull is released.

Scientifically,  【resilient】  is not the equivalent of  【elastic】 , but it may be used as its counterpart;  【elastic】  stresses the capacity for deformation without permanent injury,  【resilient】  the capacity for recovering shape or position after strain or pressure has been removed; thus, when an  【elastic】  substance is stretched or compressed, it shows itself  【resilient】  ; as arteries gradually become less  【elastic】  with age, to the same extent they become less  【resilient】 .

【Springy】  is a nontechnical term that carries the meanings and suggestions of both  【elastic】  and  【resilient】 and stresses at once the ease with which a thing yields to pressure or strain and the quickness of its return.

【Flexible】 is applicable to whatever can be bent or turned without breaking; the term may or may not imply resiliency, or quick recovery of shape.

【Supple】  applies to things which are, in general, not as solid or firm in structure as some which may be described as  【flexible】 ; it also implies ease in bending, twisting, or folding or flexing, together with resistance to accompanying injury (as from breaking, cracking, or splitting).

In extended use these words often carry the implications of their literal senses.

【Elastic】 stresses ease in stretching or expanding beyond the normal or appointed limits.

【Resilient】  implies a tendency to rebound or recover quickly (as in health or spirits) especially after subjection to stress or strain (see  【ELASTIC】 2 ).

【Springy】 , which is less common in extended use, may suggest youth, freshness, or buoyancy.

【Flexible】 implies an adaptable or accommodating quality or, when applied to persons, pliancy or tractability.

【Supple】 , in its extended use, is applied chiefly to persons or their utterances. Sometimes it suggests little more than flexibility; at other times it implies obsequiousness or complaisance or a show of these with what is actually astute mastery of a situation.