onlook vs viewing

onlook

noun
  • The act of looking on (something); observation. 

  • One's perspective or outlook. 

  • That which is looked at, regarded, or considered. 

verb
  • To look on or look at; watch; observe; view; regard. 

viewing

noun
  • An instance of viewing something. 

  • A wake. 

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