adusk vs cheerless

adusk

adj
  • Resembling conditions at dusk or twilight, low-lit, dark; in darkness, gloomy. 

adv
  • At dusk; in the dusk or twilight. 

cheerless

adj
  • Devoid of cheer; gloomy. 

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