apprehension vs understanding

apprehension

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

  • Opinion; conception; sentiment; idea. 

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

  • 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. 

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

understanding

noun
  • The act of one that understands or comprehends; comprehension; knowledge; discernment. 

  • Opinion, judgement or outlook. 

  • An informal contract; mutual agreement. 

  • A reconciliation of differences. 

  • Sympathy. 

  • Reason or intelligence, ability to grasp the full meaning of knowledge, ability to infer. 

adj
  • Showing compassion, tolerance, and forbearance. 

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