mentionable vs restriction

mentionable

adj
  • Important or worthy of note. 

  • Suitable to be openly talked about, or mentioned; not taboo. 

restriction

noun
  • A regulation or limitation that restricts. 

  • The act of restricting, or the state of being restricted. 

  • The mechanism by which a cell degrades foreign DNA material. 

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