two-edged vs uncertain

two-edged

adj
  • having two, often contrasting, meanings or interpretations 

  • having two cutting edges 

uncertain

adj
  • Unpredictable or capricious. 

  • Not certain; unsure. 

  • Not yet determined; undecided. 

  • Variable and subject to change. 

  • Fitful or unsteady. 

  • Not known for certain; questionable. 

noun
  • Something uncertain. 

How often have the words two-edged and uncertain occurred in a corpus of books? (source: Google Ngram Viewer )