What is meta stable stage?

A metastable stage refers to a state of a system that is stable under small perturbations but not under larger disturbances, meaning it can exist in a temporary equilibrium before transitioning to a more stable state. This concept is commonly encountered in physics, chemistry, and materials science, where certain phases or configurations can persist despite being energetically unfavorable. For example, in nucleation processes, a supersaturated solution can exist in a metastable state before crystals form.