assured vs unsound

assured

noun

  • An insured person. 

adj

  • Guaranteed; secure. 

  • Self-confident; self-assured; sure. 

unsound

adj

  • Not whole, not solid, defective. 

  • Infirm, diseased. 

  • Not good, unreliable. 

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