Adjective

• 1. having low density;

  "rare gasses"

  "lightheaded from the rarefied mountain air"

• 2. reserved for an elite group

• 3. of high moral or intellectual value; elevated in nature or style;

  "an exalted ideal"

  "argue in terms of high-flown ideals"- Oliver Franks

  "a noble and lofty concept"