hilltop vs outdoor

hilltop

noun
  • The peak or crest of a hill. 

outdoor

verb
  • To publicly display a child after it has been named 

adj
  • Situated in, designed to be used in, or carried on in the open air. 

  • Pertaining to charity administered or received away from, or independently from, a workhouse or other institution. 

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