interlock vs straighten

interlock

verb
  • To interlace. 

  • To fit or clasp together securely. 

noun
  • A safety device that prevents activation in unsafe conditions. 

straighten

verb
  • To clarify a situation or concept to (an audience). 

  • To bribe or corrupt. 

  • To stand up, especially from a sitting position. 

  • To cause to become straight. 

  • To become straight. 

  • To put in order; to sort; to tidy up. 

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