expansion

American  

[ik-span-shuhn] / ɪkˈspæn ʃən /

noun

• expansions
  plural

1. the act or process of expanding.

2. the state or quality of being expanded.

3. the amount or degree of expanding.

4. an expanded, dilated, or enlarged portion or form of a thing.

   The present article is an expansion of one he wrote last year.

5. anything spread out; expanse.

6. Mathematics.

   1. the development at length of an expression indicated in a contracted form, as a 2 + 2 ab + b 2 for the expression (a +b ) 2 .

   2. any mathematical series that converges to a function for specified values in the domain of the function, as 1 + x + x 2 + … for 1/(1 −x ) when x < 1.

7. Machinery. that part of the operation of an engine in which the volume of the working medium increases and its pressure decreases.

8. an increase in economic and industrial activity (opposed to contraction).

9. additional content for a video game, card game, board game, etc., that significantly expands or alters the way the game is played.

   I really improved my deck with cards from the latest expansion.

   You can play the stand-alone expansion without ever buying the original game.

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expansion British  

/ ɪkˈspænʃən /

noun

1. the act of expanding or the state of being expanded

2. something expanded; an expanded surface or part

3. the degree, extent, or amount by which something expands

4. an increase, enlargement, or development, esp in the activities of a company

5. maths

   1. the form of an expression or function when it is written as the sum or product of its terms

   2. the act or process of determining this expanded form

6. the part of an engine cycle in which the working fluid does useful work by increasing in volume

7. the increase in the dimensions of a body or substance when subjected to an increase in temperature, internal pressure, etc

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expansion Scientific  

/ ĭk-spăn′shən /

1. An increase in the volume of a substance while its mass remains the same. Expansion is usually due to heating. When substances are heated, the molecular bonds between their particles are weakened, and the particles move faster, causing the substance to expand.

2. A number or other mathematical expression written in an extended form. For example, a ² + 2 ab + b ² is the expansion of (a + b) ².

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Other Word Forms

Derived Forms

• nonexpansion
  noun
• overexpansion
  noun
• preexpansion
  noun
• reexpansion
  noun
• self-expansion
  noun
• superexpansion
  noun
• antiexpansion
  adjective
• expansional
  adjective
• expansionary
  adjective

Inflected Forms

Nouns

• expansions
  plural

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Etymology

Origin of expansion

First recorded in 1605–15; from Late Latin expānsiōn-, stem of expānsiō; equivalent to expanse + -ion

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Explanation

Expansion is what happens when something becomes bigger or more extensive. If you enjoy good pastry, you will be excited by the expansion of the bakery, but be careful or you will also see the expansion of your waistline. The noun expansion is from the Latin word expansionem, which means a spreading out. Another definition for expansion is an elaboration or expanding upon something. If you're a teacher, you might be asked to give an expansion of the short talk you give students, "Homework Stinks: But Why We Need It Anyway" to parents at the school open house.

Example Sentences

See Examples For:

expansion expansions

“We are in expansion, you don’t dismiss that, but folks are very worried,” said Susan Spence, chairman of the ISM survey.

From MarketWatch ● Nov. 2, 2026

The RatingDog China manufacturing PMI edged down to 52.0 in October from 52.1 in September, marking 11 straight months of expansion.

From The Wall Street Journal ● Nov. 2, 2026

“Through this expansion, we will maintain the momentum and success of our historic expansion last year.”

From Los Angeles Times ● Nov. 2, 2026

But its rapid expansion came at a heavy human cost.

From Barron's ● Nov. 2, 2026

The importance of rangers to the defense and expansion of the colonies increased in the decades that followed.

From "An Indigenous People’s History of the United States" by Roxanne Dunbar-Ortiz

Their goal is to investigate the earliest expansions of modern humans across Europe, including how these populations interacted with carnivores in places where bones and other organic remains are scarce.

From Science Daily ● Nov. 2, 2026

The private sector has added only about 61,000 jobs a month since November 2023, far below the 155,000 average during the 12 economic expansions between the end of World War II and the 2020 pandemic.

From MarketWatch ● Oct. 29, 2026

The Californian wanted to showcase his accomplishments: tax cuts, a budget surplus, prison reform, housing, pension reform, gasoline taxes, highway expansions, new hospitals.

From The Wall Street Journal ● Oct. 23, 2026

Vast expansions in electricity, telecommunications and production promised to connect the country and ease the tedious work of cooking, washing and cleaning.

From Los Angeles Times ● Oct. 7, 2026

Maritime technology coupled with political organization was similarly essential for European expansions to other continents, as well as for expansions of many other peoples.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

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Related Words

• development
• enlargement
• extension
• increase
• inflation
• spread

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