erstwhile vs modern

erstwhile

adj
  • Former, previous. 

  • Respected, honourable. 

modern

adj
  • Pertaining to the modern period (c.1800 to contemporary times), particularly in academic historiography. 

  • Pertaining to a current or recent time and style; not ancient. 

noun
  • Someone who lives in modern times. 

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