rar·​e·​fac·​tion | \ ˌrer-ə-ˈfak-shən \

Definition of rarefaction

1 : the action or process of rarefying
2 : the quality or state of being rarefied
3 : a state or region of minimum pressure in a medium traversed by compressional waves (such as sound waves)

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Other Words from rarefaction

rarefactional \ ˌrer-​ə-​ˈfak-​shnəl , -​shə-​nᵊl \ adjective

Examples of rarefaction in a Sentence

Recent Examples on the Web

For rarity, for sheer automotive rarefaction, the flagship of BMW’s 2 billion-euro i Division makes those cars look like link sausage. Dan Neil, WSJ, "The Avant-Garde BMW i8: Bavaria’s Answer to Tesla," 31 Aug. 2017 Here is art that turns confectionery into both rarefaction and panache. Alastair Macaulay, New York Times, "On the Frivolities of Ballet, the Contradictory Art," 19 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rarefaction.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of rarefaction

1572, in the meaning defined at sense 1

History and Etymology for rarefaction

French or Medieval Latin; French raréfaction, from Medieval Latin rarefaction-, rarefactio, from Latin rarefacere to rarefy

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Time Traveler for rarefaction

The first known use of rarefaction was in 1572

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rar·​e·​fac·​tion | \ ˌrar-ə-ˈfak-shən, ˌrer- \

Medical Definition of rarefaction

1 : the action or process of rarefying
2 : the quality or state of being rarefied especially : an increase in porosity areas of rarefaction in the bones
3 : a state or region of minimum pressure in a medium transversed by compressional waves (as sound waves) the eardrum vibrates according to the compressions and rarefactions of the sound wave

Other Words from rarefaction

rarefactional \ -​shnəl, -​shən-​ᵊl \ adjective

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More from Merriam-Webster on rarefaction

Rhyming Dictionary: Words that rhyme with rarefaction

Nglish: Translation of rarefaction for Spanish Speakers

Britannica.com: Encyclopedia article about rarefaction

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