overburden vs saturate

overburden

verb
  • To overload or overtax. 

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. 

saturate

verb
  • To fill to excess. 

  • To cause to become completely impregnated, or soaked (especially with a liquid). 

  • To satisfy the affinity of; to cause a substance to become inert by chemical combination with all that it can hold. 

  • To render pure, or of a colour free from white light. 

adj
  • Very intense. 

  • Saturated; wet. 

noun
  • Something saturated, especially a saturated fat. 

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