equilibrium

noun

equi·​lib·​ri·​um ˌē-kwə-ˈli-brē-əm  ˌe- 

plural equilibriums or equilibria ˌē-kwə-ˈli-brē-ə 

ˌe-

1

a

: a state of intellectual or emotional balance : poise

trying to recover his equilibrium

b

: a state of adjustment between opposing or divergent influences or elements

2

: a state of balance between opposing forces or actions that is either static (as in a body acted on by forces whose resultant is zero) or dynamic (as in a reversible chemical reaction when the rates of reaction in both directions are equal)

3

: balance sense 3a

Did you know?

Equilibrium contains a root from the Latin libra, meaning "weight" or "balance". As a constellation, zodiac symbol, and astrological sign, Libra is usually pictured as a set of balance scales, often held by the blindfolded goddess of justice, which symbolizes fairness, equality, and justice. Equilibrium has special meanings in biology, chemistry, physics, and economics, but in all of them it refers to the balance of competing influences.

Synonyms

• balance
• counterpoise
• equilibration
• equipoise
• poise
• stasis

Examples of equilibrium in a Sentence

Supply and demand were in equilibrium.

we must find an equilibrium between commercial development and conservation of our natural treasures

Recent Examples on the Web

In any event, this is the kind of thing that, in the past, has ignited bloody internecine wars that end up killing lots and lots of people before a new equilibrium is achieved. —Eduardo Porter, Washington Post, 30 July 2024

Generally, it's understood to mean a person who is harmful to another's emotional equilibrium. —Susan Adcox, Parents, 22 July 2024

This struggle creates a tension that keeps the whole system in equilibrium and prevents unscrupulous office holders from using their authority inappropriately. —Chris Roemer, Baltimore Sun, 21 July 2024

The Nash equilibrium is the only strategy that is not susceptible to exploitation. —Jack Murtagh, Scientific American, 16 July 2024

Word History

Etymology

Latin aequilibrium, from aequilibris being in equilibrium, from aequi- + libra weight, balance

First Known Use

1608, in the meaning defined at sense 1a

Phrases Containing equilibrium

• equilibrium constant
• punctuated equilibrium

Kids Definition

equilibrium

noun

equi·​lib·​ri·​um ˌē-kwə-ˈlib-rē-əm 

ˌek-wə-

plural equilibriums or equilibria -rē-ə 

1

: a state of balance between opposing forces or actions

2

: the normal balanced state of the body of an animal that is maintained in relation to the forces (as gravity) acting on it and to things in the environment (as the surface on which life is lived) and that is sensed and checked by the inner ear of vertebrates including human beings

Etymology

from Latin aequilibrium "state of being in balance," from aequus "equal" and libra "weight, balance, scales" — related to deliberate, libra

Medical Definition

equilibrium

noun

equi·​lib·​ri·​um ˌē-kwə-ˈlib-rē-əm  ˌek-wə- 

plural equilibriums or equilibria -rē-ə 

1

: a state of balance between opposing forces or actions that is either static (as in a body acted on by forces whose resultant is zero) or dynamic (as in a reversible chemical reaction when the velocities in both directions are equal)

2

: a state of intellectual or emotional balance