Definition of rarefy in English:


(also rarify)


  • Make or become less dense or solid.

    [with object] ‘air rarefies and degrounds the physical body’
    [no object] ‘as the shell continues to expand and rarefy, astronomers may eventually be able to see characteristic gamma rays from the radioactivity within’
    • ‘Well, it sounds like it, or at least the particularly rarified form of it practiced by the kind of names mentioned above.’
    • ‘Companies profit from collectors by creating limited editions of a particular item and releasing different versions of their products in different continents to rarify their commodities, thus increasing their value.’
    • ‘‘Humidity means that the air density is rarified and so the available engine power is reduced as air entering the combustion chamber is reduced,’ says Binotto.’
    • ‘But more than anything yet seen in Moore's career, this film was made in the bubble and breathes truly rarified air.’
    • ‘Thus began Cooper's serendipitous ascent into the more rarified air of the arts and crafts.’
    • ‘It wasn't quite as rarefied as Royal Ascot, and the weather was dodgy to say the least, but it was still fun to go racing at Ayr.’
    • ‘I know the air is pretty rarified in academia, but has the good professor considered taking an evening course in the university of life?’
    • ‘Changes in the game might have rarified some of old-time hockey's staple techniques, but what of the future?’
    • ‘In most cases, such concentrations of atoms are so rarefied that the chances of colliding are infinitesimal.’
    • ‘He noticed worriedly that the overcrowded pool area felt overly warm and thought that the air was rarified.’
    • ‘Sound waves propagate through such materials by periodically compressing and rarefying the medium.’
    • ‘I find that if I concentrate on the geometric shapes and unfocus to the point of occular agony they rarify into a twisting tunnel.’
    • ‘In the inner heartwood, these bodies were rarefying and cell walls became impregnated by a brown colour.’
    • ‘However, member countries are not likely to rarify agriculture's inclusion until key implementation issues are resolved.’
    • ‘Or it could rarify the nature of ritual objects, so that they must be of some degradable quality (such as the raw clay used in many Hindi rites).’
    • ‘It's one of those rarified treats when you are simply left reaching for words.’
    • ‘In order to maintain value or currency, beauty/art must be exclusionary, standardized and rarified.’
    • ‘The air here isn't that rarified and most of us like to do other things as well.’
    • ‘Law, it is well known, filters and rarefies the halo of horror and suffering surrounding crimes.’
    • ‘The White House press corps is the most rarefied of American journalistic beats.’
    purify, clarify, clear, cleanse, strain, sift, filter, rarefy, distil, concentrate, process, treat
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Late Middle English: from Old French rarefier, or medieval Latin rareficare, based on Latin rarus rare + facere make.