submissive vs unimpressible

submissive

adj

  • Meekly obedient or passive. 

noun

  • One who submits. 

  • One who submits to a dominant partner in BDSM practices. 

unimpressible

adj

  • Not impressible; not sensitive; apathetic. 

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