perm vs sorting

perm

noun

  • A permutation. 

  • Permission 

  • A combination of outcomes (not a permutation) that a gambler bets on in the football pools. 

verb

  • To give hair a perm, using heat, chemicals etc. 

sorting

noun

  • Categorizing. 

  • Ordering. 

  • Mending. 

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