importunate vs split-second

importunate

verb
  • To importune, or to obtain by importunity. 

adj
  • Persistent or pressing, often annoyingly so. 

  • Given to importunate demands, greedily or thoughtlessly demanding. 

split-second

noun
  • The nick of time; a brief moment. 

How often have the words importunate and split-second occurred in a corpus of books? (source: Google Ngram Viewer )