brooding vs engrossment

brooding

noun
  • A spell of brooding; the time when someone broods. 

adj
  • Broody; incubating eggs by sitting on them. 

  • Deeply or seriously thoughtful. 

engrossment

noun
  • The state of being engrossed; concentration or preoccupation. 

  • The fact or instance of preparing the final draft legal document for execution or completion. 

  • Such document that has not yet been executed or completed. 

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