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1. The condition of being rarefied.
a. A decrease in density and pressure in a medium, such as air, caused by the passage of a sound wave.
b. The region in which this occurs.

rar′e·fac′tive adj.


(ˌrɛərɪˈfækʃən) or


the act or process of making less dense or the state of being less dense
ˌrareˈfactional, ˌrarefiˈcational, ˌrareˈfactive adj


(ˌrɛər əˈfæk ʃən)

1. the act or process of rarefying.
2. the state of being rarefied.
rar`e•fac′tion•al, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rarefaction - a decrease in the density of something; "a sound wave causes periodic rarefactions in its medium"
concentration - increase in density


[ˌrɛərɪˈfækʃən] Nrarefacción f


nDünne f; (fig)Exklusivität f
References in classic literature ?
For some days past, Captain Bonneville had been made sensible of the great elevation of country into which he was gradually ascending by the effect of the dryness and rarefaction of the atmosphere upon his wagons.
This novel type of data will be analysed using a new rarefaction method, developed to test mechanistic explanations for biodiversity patterns along ecological gradients.
Based on the OTUs, rarefaction curve and alpha diversity indexes (i.
Beaucoup d'intentions ont ete contrariees par la rarefaction des assiettes de terrain.
It is obvious, that when the piston moves down the rarefaction is caused, which intakes the liquid drug into the vessels.
Since the decoding of the human genome and with the pressure of the rarefaction of the fossil resources (hydrocarbon, oil), the biomass, extraordinary sources of renewable carbon, constitute a huge reserve of raw materials in industries such as: chemistry, biofuel, paper, textile and food.
Apres avoir insiste sur une gestion [beaucoup moins que]optimale et durable[beaucoup plus grand que] de la problematique de l'eau aux besoins de developpement, la ministre a fait constater que les ressources hydriques dans le bassin [beaucoup moins que]sont limitees voire en rarefaction continue[beaucoup plus grand que] sous l'effet de plusieurs facteurs, citant les changements climatiques et les besoins pressants lies a la croissance demographique et aux activites industrielles.
Expected and observed heterozygosities in each group were calculated using HW-Quickcheck (Kalinowski 2006), whereas both allele counts and allelic richness after rarefaction were estimated using HP-Rare (Kalinowski 2005).
Increased cellular senescence and vascular rarefaction exacerbate the progression of kidney fibrosis in aged mice following transient ischemic injury.
Since bird abundances were different among the different habitats we used rarefaction to explore if differences in richness and diversity were closely related to abundance.
Species rarefaction curves were calculated for the Pennsylvania and New York collections individually and for both states combined using EstimateS (Colwell 2005).
In order to characterize diatom diversity, we calculated species richness using rarefaction analysis in R (Heck et al.