equilibrated

Equilibrated is an adjective used to describe a system or substance that has reached a state of equilibrium or has been brought into such a state. In this condition, macroscopic properties such as composition, temperature, pressure, or concentration do not change with time, or change only negligibly in the presence of ongoing microscopic processes that balance each other.

Etymology: The word comes from the Latin aequilibratus, from aequus (equal) and libra (balance). In English it has been used since the 18th century to denote balance between opposing forces or processes and, by extension, stabilization of a system.

Contexts: In chemistry and thermodynamics, an equilibrated mixture is one in which the forward and reverse reaction rates are equal, yielding constant concentrations described by the equilibrium constant. In physics and material science, thermal equilibration occurs when a system and its surroundings share a common temperature. In biology and physiology, equilibration can refer to the steady-state distribution of ions or metabolites across compartments after equilibration with bodily fluids.

Usage: Equilibrated is the past participle of equilibrate and is used attributively (an equilibrated solution) or predicatively (the system equilibrated quickly). Related terms include equilibrium, equilibration, and equilibrating.