[rair-uh-fak-shuh n] /ˌrɛər əˈfæk ʃən/
the act or process of .
the state of being .
the act or process of making less dense or the state of being less dense
c.1600, from Middle French raréfaction or directly from Medieval Latin rarefactionem (nominative rarefactio), noun of action from past participle stem of Latin rarefacere (see rarefy). Used chiefly in reference to gasses.
rarefaction rar·e·fac·tion (râr’ə-fāk’shən)
A decrease in density and pressure in a medium, such as air, caused by the passage of a sound wave.
[rair-uh-fahyd] /ˈrɛər əˌfaɪd/ adjective 1. extremely high or elevated; lofty; exalted: the rarefied atmosphere of a scholarly symposium. 2. of, belonging to, or appealing to an exclusive group; select; esoteric: rarefied tastes. [rair-uh-fahy] /ˈrɛər əˌfaɪ/ verb (used with object), rarefied, rarefying. 1. to make rare or rarer; make less dense: to rarefy a gas. 2. […]
[rair-uh-fahy] /ˈrɛər əˌfaɪ/ verb (used with object), rarefied, rarefying. 1. to make rare or rarer; make less dense: to rarefy a gas. 2. to make more refined, spiritual, or exalted. verb (used without object), rarefied, rarefying. 3. to become rare or less dense; become thinned: Moisture rarefies when heated. /ˈrɛərɪˌfaɪ/ verb -fies, -fying, -fied 1. […]
- Rare gas
noun 1. another name for inert gas (sense 1)
[rair-lee] /ˈrɛər li/ adverb 1. on occasions; infrequently; seldom: I’m rarely late for appointments. 2. exceptionally; in an unusual degree. 3. unusually or remarkably well; excellent. /ˈrɛəlɪ/ adverb 1. hardly ever; seldom: I’m rarely in town these days 2. to an unusual degree; exceptionally 3. (dialect) uncommonly well; excellently: he did rarely at market yesterday […]