abluent vs purgative

abluent

adj

  • Washing away; carrying off impurities; detergent. 

noun

  • A detergent. 

purgative

adj

  • purging 

noun

  • something, such as a substance or medicine, that purges; laxative 

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