trustless vs unsound

trustless

adj
  • Lacking trust; untrusting. 

  • Which does not need any trust, or a trusted third party. 

unsound

adj
  • Not good, unreliable. 

  • Not whole, not solid, defective. 

  • Infirm, diseased. 

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