overburden vs repress

overburden

noun
  • A sterile stratum that lies above the stratum being investigated 

  • The rock and subsoil that lies above a mineral deposit such as a coal seam. 

verb
  • To overload or overtax. 

repress

verb
  • To check; to keep back. 

  • To press again. 

  • To forcefully prevent an upheaval from developing further. 

noun
  • A record pressed again; a repressing. 

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