booster cushion vs pillow

booster cushion

pillow

verb
  • To rest as on a pillow. 

noun
  • A soft cushion used to support the head in bed. 

  • A pillow lava. 

  • The socket of a pivot. 

  • A block under the inner end of a bowsprit. 

  • A kind of plain, coarse fustian. 

  • A piece of metal or wood, forming a support to equalize pressure; a brass; a pillow block. 

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