lye vs sugar soap

lye

noun
  • An alkaline liquid made by leaching ashes (usually wood ashes). 

  • A short side line, connected with the main line; a turn-out; a siding. 

  • Potassium or sodium hydroxide (caustic soda). 

verb
  • To treat with lye. 

sugar soap

noun
  • An extremely powerful detergent used for washing surfaces prior to painting. 

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