mopping vs stewardship

mopping

noun
  • The process of cleaning with a mop. 

  • An application of molten asphalt to a roof etc. 

stewardship

noun
  • The rank or office of a steward. 

  • Foresters believe in stewardship of the land. 

  • The act of caring for or improving with time. 

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