dolour vs groaning

dolour

noun
  • Anguish, grief, misery, or sorrow. 

  • In economics and utilitarianism: a unit of pain used to theoretically weigh people's outcomes. 

groaning

noun
  • A low sound associated with extended suffering, sorrow, and toil. 

adj
  • Heavily laden, as if to creak under the strain. 

  • That groans. 

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