apprehension vs assurance

apprehension

noun
  • 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. 

  • 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. 

assurance

noun
  • Firmness of mind; undoubting steadiness; intrepidity; courage; confidence; self-reliance. 

  • Subjective certainty of one's salvation. 

  • The act of assuring; a declaration tending to inspire full confidence; something designed to give confidence. 

  • Insurance; a contract for the payment of a sum on occasion of a certain event, as loss or death. Assurance is used in relation to life contingencies, and insurance in relation to other contingencies. It is called temporary assurance, in the time within which the contingent event must happen is limited. 

  • The state of being assured; total confidence or trust; a lack of doubt; certainty. 

  • Excessive boldness; impudence; audacity 

  • Any written or other legal evidence of the conveyance of property; a conveyance; a deed. 

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