System persistence achieved by incorporation of non-equilibrium processes at lower level into quasi-equilibrium patterns and processes at the higher level. A property of hierarchies that has a wicked ability to confuse discussions about stability of ecological systems.

the quality of a physical system that persists in its existing equilibrium when undisturbed (or only slightly disturbed) but able to pass to a more stable equilibrium when sufficiently disturbed

The state of a bi-stable device when the input transitions violate setup and hold time restrictions occurring during a narrow timing window. The bi-stable flip-flop can enter a balanced transitory state called “meta-stable.

The academic definition of metastability is the zone in a solubility curve where there is supersaturation but no spontaneous nucleation or crystallization. A more practical form of metastability is the zone where growth exceeds nucleation; beyond this, most systems will not produce the large single crystals desired in industry.