imperious vs low-key

imperious

adj
  • Domineering, arrogant, or overbearing. 

  • Urgent. 

low-key

adj
  • Restrained, subtle, not trying to attract attention. 

  • Dark; characterised by dark tones and muted colours. 

adv
  • Kind of. 

  • In a low-key or surreptitious manner; secretively; on the down-low. 

How often have the words imperious and low-key occurred in a corpus of books? (source: Google Ngram Viewer )