starch vs toughen up

starch

noun
  • Fortitude. 

  • Carbohydrates, as with grain and potato based foods. 

  • A stiff, formal manner; formality. 

  • Any of various starch-like substances used as a laundry stiffener 

  • A widely diffused vegetable substance, found especially in seeds, bulbs and tubers, as extracted (e.g. from potatoes, corn, rice, etc.) in the form of a white, glistening, granular or powdery substance, without taste or smell, and giving a very peculiar creaking sound when rubbed between the fingers. It is used as a food, in the production of commercial grape sugar, for stiffening linen in laundries, in making paste, etc. 

verb
  • To apply or treat with laundry starch, to create a hard, smooth surface. 

adj
  • Stiff; precise; rigid. 

toughen up

verb
  • To make or become mentally tougher. 

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