potent vs spinning one’s wheels

potent

noun
  • A heraldic fur formed by a regular tessellation of blue and white T shapes. 

adj
  • Able to procreate. 

  • Very powerful or effective. 

  • Having a sharp or offensive taste. 

  • Possessing strength. 

  • Powerfully effective. 

spinning one’s wheels

How often have the words potent and spinning one’s wheels occurred in a corpus of books? (source: Google Ngram Viewer )