equation

noun

equa·​tion i-ˈkwā-zhən 

 also  -shən

1

a

: the act or process of equating

b(1)

: an element affecting a process : factor

(2)

: a complex of variable factors

c

: a state of being equated

specifically : a state of close association or identification

bring governmental enterprises and payment for them into immediate equation

—R. G. Tugwell

2

a

: a usually formal statement of the equality or equivalence of mathematical or logical expressions

b

: an expression representing a chemical reaction quantitatively by means of chemical symbols

Examples of equation in a Sentence

the equation of material wealth with happiness

Recent Examples on the Web

That has been made clear by both sides of the Heat/Suns equation. —Ira Winderman, Sun Sentinel, 23 June 2025

The photos of the prototype show shocks at each wheel for a smooth ride, a headlight and LED strip light to the front while the renders add turn signaling and a braking tail-light to the safety equation. —Paul Ridden june 22, New Atlas, 22 June 2025

There are myriad other factors in the equation, from availability of raw materials (many of which are still sourced from Asia or Europe), to staffing (workers must be trained on robotics and electronics), and facilities, which must be equipped to support the machinery and its output. —Kate Nishimura, Sourcing Journal, 20 June 2025

The magnus force that normally influences a baseball’s trajectory is removed from the equation. —Cody Stavenhagen, New York Times, 19 June 2025

Word History

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing equation

• characteristic equation
• cubic equation
• differential equation
• Diophantine equation
• enter (into) the equation
• equation of time
• linear equation
• parametric equation
• partial differential equation
• personal equation
• quadratic equation
• Schrödinger equation
• simple equation
• wave equation

Rhymes for equation

• abrasion
• caucasian
• eurasian
• evasion
• invasion
• occasion
• persuasion
• asian
• suasion
• athanasian

Kids Definition

equation

noun

equa·​tion i-ˈkwā-zhən 

 also  -shən

1

: the act or process of equating : the state of being equated

2

a

: a statement of the equality of two mathematical expressions

b

: an expression involving chemical symbols for a chemical reaction

Medical Definition

equation

noun

equa·​tion

i-ˈkwā-zhən also -shən

: an expression representing a chemical reaction quantitatively by means of chemical symbols