antacid vs permeable

antacid

adj
  • Counteracting or neutralizing acidity, especially in the stomach. 

noun
  • An agent that counteracts or neutralizes acidity, especially in the stomach. 

permeable

adj
  • absorbing or allowing the passage of fluids 

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