grown-up vs youthless

grown-up

adj
  • Adult, physically mature. 

  • Of, pertaining to, or suitable for adults. 

  • Having a mature outlook. 

noun
  • An adult. 

youthless

adj
  • Devoid of youth; old, aged. 

How often have the words grown-up and youthless occurred in a corpus of books? (source: Google Ngram Viewer )