verb
Freq #1075665
Meanings
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1
verb
to make a gas thinner or less dense
Heating the enclosed air will rarefy it and lower its density.
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2
verb
to make something more refined, subtle, or specialized
Years of debate began to rarefy the theory into a form understood by only a few specialists.
Thesaurus
Etymology
From Middle English rarefien and Old French rarefier, from Latin rarefacere 'to make rare or thin', combining rarus 'thinly spaced, rare' with facere 'to make'. The figurative sense extends physical thinning to intellectual refinement.