buttercup vs preemie

buttercup

noun
  • Affectionate or ironic term of address. 

  • Any of many herbs, of the genus Ranunculus, having yellow flowers; the crowfoot. 

  • Any flower of the genus Narcissus; a daffodil. 

preemie

noun
  • A baby that has been born prematurely 

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