Rarefy
verb ·Uncommon ·College level
Definitions
- 1 To make rare, thin, porous, or less dense. transitive
"By means of this gauge, Mr. Smeaton judged that his machine was incomparably better than any former one, as it seemed to rarefy the air in the receiver 1000, or even 2000 times, while the best of these only rarefied it about 140[…]"
- 2 weaken the consistency of (a chemical substance) wordnet
- 3 To become rare, thin or less dense. intransitive
"For if The^([sic]) water rarefies and then Condenses, all that great mass of water of the Lake of the Ilinois rises in its vast basin when it rarefies, and falls when it condenses. And, as water always rises as much as it falls, it would[…]"
- 4 make more subtle or refined wordnet
- 5 lessen the density or solidity of wordnet
Antonyms
All antonymsExample
More examples"By means of this gauge, Mr. Smeaton judged that his machine was incomparably better than any former one, as it seemed to rarefy the air in the receiver 1000, or even 2000 times, while the best of these only rarefied it about 140[…]"
Etymology
From Middle English rarefien, from Old French rarefier (French raréfier), from Latin rarefacere (“make rare”). By surface analysis, rare + -fy.
More for "rarefy"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.