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Added 10 October 2026

rarefaction

noun

noun Definition from WordNet 3.1, Princeton University. More about rarefaction at Wordnik → Where our words come from →

A decrease in the density of something.
a sound wave causes periodic rarefactions in its medium

Origin

From Middle French raréfaction. By surface analysis, rarefy + -faction.

From Wiktionary, via Kaikki.org (CC BY-SA)

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