rarefied \RAIR-uh-fahyd\, 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.
A fire then being made in any chimney, the air over the fire is rarefied by the heat, becomes lighter and therefore immediately rises in the funnel, and goes out...
-- Benjamin Franklin, "Observations and Experiments," 1744-1785
She and Adam had one thing in common--they were both fine-drawn and rarefied--not much clogged with fleshly appetites.
-- John Buchan, "A Prince of Captivity," 1933
Rarefied entered English in the late 1300s from the Latin rarus + facere meaning "to make rare."
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