doublespeak vs slanguage

doublespeak

noun
  • Any language deliberately constructed to disguise or distort its actual meaning, often by employing euphemism or ambiguity. 

slanguage

noun
  • A particular vernacular or vocabulary of slang; the jargon or lingo of a particular group. 

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