dampen vs decrease

dampen

verb
  • To lessen; to dull; to make less intense (said of emotions and non-physical things). 

  • To become damped or deadened. 

  • To become damp or moist. 

  • To make damp or moist; to make moderately wet. 

decrease

verb
  • To make (a quantity) smaller. 

  • Of a quantity, to become smaller. 

noun
  • A reduction in the number of stitches, usually accomplished by suspending the stitch to be decreased from another existing stitch or by knitting it together with another stitch. See Decrease (knitting). 

  • An amount by which a quantity is decreased. 

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