Meaning of EXPANSION in English

I. ikˈspanchən, ek-, -paan- noun

( -s )

Etymology: Late Latin expansion-, expansio, from Latin expansus + -ion-, -io -ion

1. : the act or process of expanding: as


(1) : the act or process of spreading out

the easy expansion of the wing of a bird — Nehemiah Grew

(2) : the mushrooming of a bullet upon striking the target


(1) : the act or process of increasing in extent, size, number, volume, or scope : enlargement , growth

localized pain along nerve trunks may be due to the expansion of the dissolved nitrogen without actual bubble formation — H.G.Armstrong

the bewildering expansion of science during the last century — C.H.Grandgent

this desire for territorial expansion is deeply rooted in human history — C.J.Friedrich

(2) in an electronic sound amplifier : the widening of the range of an audio-frequency signal by making the gain vary directly with the amplitude of the input signal so that weak sounds become weaker and loud sounds louder


(1) : the act of expressing fully or of developing in detail : amplification

these lectures with some slight expansion … are here printed as delivered — A.N.Whitehead

(2) mathematics : the developed result of an indicated or possible operation : the expression of a function in the form of a series

the expansion of ( a+b ) 2 is a 2 +2 ab+b 2

(3) logic : the operation or result of making the terms in a formula more explicit or of introducing new terms without changing the logical significance of the expression

2. : the quality or state of being expanded

the gilded clouds in fair expansion lie — Alexander Pope

3. : expanse

the sky's serene expansion — Thomas Hood †1845

4. obsolete : pure space

lost in expansion , void and infinite — Richard Blackmore


a. : the increase in volume of working fluid (as steam) in an engine cylinder after cutoff or in an internal-combustion engine after explosion by which it continues to propel the piston while expending part of its internal energy and losing in pressure and temperature

b. : the period during which such expansion occurs

c. : amount of increase of length, area, or volume


a. : an expanded part

the great expansion of the St. Lawrence called the Lake of St. Peter — Francis Parkman

b. : something that results from an act of expanding

this book was an expansion of a notable series of articles — A.C.Ames

7. : expansiveness

gradually tones of careless freedom, moments of reckless expansion come in, though never … any trace of sentimentality or of adoration — Havelock Ellis

II. noun

Usage: often attributive

: the addition of one or more teams to a sports league

an expansion team

an expansion year

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.