ethereal vs substantial

ethereal

adj
  • Pertaining to the (real or hypothetical) upper, purer air, or to the higher regions beyond the earth or beyond the atmosphere. 

  • Consisting of ether; hence, exceedingly light or airy; tenuous; spiritlike; characterized by extreme delicacy, as form, manner, thought, etc. 

  • To do with diethyl ether. 

  • Pertaining to the immaterial realm, as symbolically represented by, or (in earlier epochs) conflated with, such atmospheric and extra-atmospheric concepts. 

substantial

adj
  • Most important; essential. 

  • Not imaginary; real; actual; true; veritable. 

  • Having a substance; actually existing. 

  • Corporeal; material; firm. 

  • Possessed of goods or an estate; moderately wealthy. 

  • Satisfying; having sufficient substance to be nourishing or filling. 

  • Large in size, quantity, or value; ample; significant. 

  • Having good substance; strong; stout; solid; firm. 

noun
  • Anything having substance; an essential part. 

How often have the words ethereal and substantial occurred in a corpus of books? (source: Google Ngram Viewer )