affiance vs plight

affiance

verb
  • To be betrothed to; to promise to marry. 

noun
  • Faith, trust. 

plight

verb
  • Specifically, to pledge (one's troth etc.) as part of a marriage ceremony. 

  • To promise (oneself) to someone, or to do something. 

noun
  • Blame; culpability; fault; wrong-doing; sin; crime. 

  • One's office; duty; charge. 

  • Responsibility for ensuing consequences; risk; danger; peril. 

  • A dire or unfortunate situation. 

  • An instance of danger or peril; a dangerous moment or situation. 

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