endowment vs heirship

endowment

noun
  • Something with which a person or thing is endowed. 

  • Property or funds invested for the support and benefit of a person or not-for-profit institution. 

  • Endowment assurance or pure endowment. 

  • A ceremony designed to prepare participants for their role in the afterlife. 

heirship

noun
  • The status of being heir to something or someone 

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