safety vs unwind

safety

noun
  • A mechanism on a weapon or dangerous equipment designed to prevent accidental firing. 

  • An instance of a player being sacked or tackled in the end zone, or stepping out of the end zone and off the field, resulting in two points to the opposite team. 

  • The condition or feeling of being safe; security; certainty. 

  • Any of the defensive players who are in position furthest from the line of scrimmage and whose responsibility is to defend against passes as well as to be the tacklers of last resort. 

  • A safety squeeze. 

  • Preservation from escape; close custody. 

verb
  • to secure a firing pin, as in guns, to keep the gun from firing 

  • To secure (a mechanical component, as in aviation) to keep it from becoming detached even under vibration. 

unwind

noun
  • Any mechanism or operation that unwinds something. 

verb
  • To undo something. 

  • To relax; to chill out; to rest and become relieved of stress 

  • To close out a position, especially a complicated position. 

  • To be or become unwound; to be capable of being unwound or untwisted. 

  • To analyse (a call stack) so as to generate a stack trace etc. 

  • To separate (something that is wound up) 

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