Metastable state
From Soft-Matter
Introduction
A metastable state is a state of a system which is stable over one time-scale and unstable over another timescale. It represents a local, but not global, minimum in the energy landscape of the system.

Depiction of metastable state where state 1 is the metastable state, state 2 is the transition state, and state 3 is the stable state. (Image from Wikipedia)