explicit vs unheard

explicit

adj
  • Very specific, clear, or detailed. 

  • Containing material (e.g. language or film footage) that might be deemed offensive or graphic. 

noun
  • The final few words of a text. 

unheard

adj
  • Not heard. 

  • Not listened to. 

  • Not known to fame; not illustrious or celebrated; obscure. 

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