bedspread vs duvet

bedspread

noun
  • The topmost covering of a bed, often functioning as a blanket. 

  • A coverlet. 

duvet

noun
  • A quilt or usually flat cloth bag with a filling (traditionally down) and usually an additional washable cover, used instead of blankets; often called a comforter or quilt, especially in US English. 

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