substantial vs unsound

substantial

noun
  • Anything having substance; an essential part. 

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. 

unsound

adj
  • Not whole, not solid, defective. 

  • Infirm, diseased. 

  • Not good, unreliable. 

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