guardianship vs safekeeping

guardianship

noun
  • The office or position of one acting as a guardian or conservator, especially in a legal capacity. 

safekeeping

noun
  • the responsibility of a guardian 

  • the act of keeping something safe; protection from harm, damage, loss, or theft 

  • not returning checks; a system wherein banks keep checks (cheques) that people write, rather than returning them to the account holder with their monthly statement. 

  • the storage of assets in a protected area 

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