angst vs apprehension

angst

noun
  • A feeling of acute but vague anxiety or apprehension often accompanied by depression, especially philosophical anxiety. 

  • Emotional turmoil; painful sadness. 

verb
  • To suffer angst; to fret. 

apprehension

noun
  • Anticipation, especially of unfavorable things such as dread or fear or the prospect of something unpleasant in the future. 

  • Opinion; conception; sentiment; idea. 

  • The faculty by which ideas are conceived or by which perceptions are grasped; understanding. 

  • The physical act of seizing or taking hold of (something); seizing. 

  • Perception; the act of understanding using one's intellect without affirming, denying, or passing any judgment 

  • The act of seizing or taking by legal process; arrest. 

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