ixnay vs pass up

ixnay

verb
  • To reject something. 

noun
  • Nothing; nix; often in the phrase "ixnay on ...", indicating something that must not be mentioned, often in Pig Latin 

intj
  • No. 

pass up

verb
  • To refuse (not accept); forgo. 

  • Used other than figuratively or idiomatically: see pass, up. 

  • To submit (hand in) items to a person, usually one's teacher. 

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