ingression vs outset

ingression

noun
  • The act or process of entering or intruding. 

  • The process by which a potentiality enters into actuality. 

  • The inward migration of cells from the blastula during gastrulation. 

outset

noun
  • Onset; the beginning or initial stage of something. 

verb
  • To cause (a design element) to extend around the outside of something else, the opposite of being inset. 

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