unbeatable vs unpassable

unbeatable

adj
  • That cannot be beaten, defeated or overcome 

noun
  • Someone or something that can't be beaten 

unpassable

adj
  • Not able to be passed; not capable of being beaten at the net by a passing shot. 

  • Not able to be passed. 

  • Unable to pass successfully as the gender one wishes to be seen as. 

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