secure vs vary

secure

verb
  • To put beyond hazard of losing or of not receiving; to make certain; to assure; frequently with against or from, or formerly with of. 

  • To make fast; to close or confine effectually; to render incapable of getting loose or escaping. 

  • To get possession of; to make oneself secure of; to acquire certainly. 

  • To make safe; to relieve from apprehensions of, or exposure to, danger; to guard; to protect. 

adj
  • Free from the danger of theft; safe. 

  • Certain to be achieved or gained; assured. 

  • Free from attack or danger; protected. 

  • Free from the risk of eavesdropping, interception or discovery; secret. 

  • Confident in opinion; not entertaining, or not having reason to entertain, doubt; certain; sure; commonly used with of. 

  • Free from anxiety or doubt; unafraid. 

  • Free from the risk of financial loss; reliable. 

  • Firm and not likely to fail; stable. 

vary

verb
  • To be or act different from the usual. 

  • To make of different kinds; to make different from one another; to diversity; to variegate. 

  • To embellish; to change fancifully; to present under new aspects, as of form, key, measure, etc. See variation. 

  • Not to remain constant: to change with time or a similar parameter. 

  • To institute a change in, from a current state; to modify. 

  • To change with time or a similar parameter. 

  • To display differences. 

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