relevant vs unignorable

relevant

adj
  • Related, connected, or pertinent to a topic. 

  • Directly related, connected, or pertinent, with important ramifications or implications. 

  • Not out of date; current. 

unignorable

adj
  • That cannot be ignored. 

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