confound vs obfuscate

confound

verb
  • To fail to see the difference; to mix up; to confuse right and wrong. 

  • To combine in a confused fashion; to mingle so as to make the parts indistinguishable. 

  • To stun or amaze. 

  • To make something worse. 

  • To cause to be ashamed; to abash. 

  • To defeat, to frustrate, to thwart. 

  • To perplex or puzzle. 

noun
  • A confounding variable. 

obfuscate

verb
  • To deliberately make more confusing in order to conceal the truth. 

  • To alter code while preserving its behavior but concealing its structure and intent. 

  • Before leaving the scene, the murderer set a fire in order to obfuscate any evidence of their identity. 

  • To make dark; to overshadow. 

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