menial vs under someone's heel

menial

adj
  • Of or relating to unskilled work. 

  • Servile; low; mean. 

  • Of or relating to work normally performed by a servant. 

noun
  • A servant, especially a domestic servant. 

  • A person who has a subservient nature. 

under someone's heel

How often have the words menial and under someone's heel occurred in a corpus of books? (source: Google Ngram Viewer )