expansion

[ik-span-shuhn]

noun

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 (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.

expansion

/ 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

expansion

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.

Other Word Forms

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

Word History and Origins

Origin of expansion¹

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

Example Sentences

OMB’s expansion of racial/ethnic categories has consequences.

Read more on The Wall Street Journal

The crucial difference was the expansion of tariff relief on imported auto parts, House said.

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Gaudenzi called the expansion to 10 events "a proud moment for us and the result of a journey that's been years in the making".

Read more on Barron's

Southwest expects a record quarterly operating revenue and meaningful margin expansion in the fourth quarter.

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When borrowing costs fall, small businesses revisit expansion plans, homeowners consider renovations and manufacturers weigh capital investments that had been shelved.

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Related Words

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