infiltrate vs lixiviate

infiltrate

verb
  • To cause (a liquid) to pass through something by filtration. 

  • To cause to penetrate in this way. 

  • To invade or penetrate a tissue or organ. 

  • To surreptitiously penetrate, enter or gain access to. 

  • To send (soldiers, spies, etc.) through gaps in the enemy line. 

  • To pass through something by filtration. 

  • To move from a vein, remaining in the body. 

noun
  • Any undesirable substance or group of cells that has made its way into part of the body. 

lixiviate

verb
  • To separate (a substance) into soluble and insoluble components through percolation; to leach. 

noun
  • leachate 

adj
  • Impregnated with salts from wood ashes. 

  • Of or relating to lye or lixivium; of the quality of alkaline salts. 

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