aigrette vs covert

aigrette

noun
  • A feather or plume, or feather-shaped item, used as an adornment or ornament. 

  • The lesser white heron. 

  • The feathery crown of some seeds (such as the dandelion). 

covert

noun
  • A feather that covers the bases of flight feathers. 

  • A covering. 

  • A disguise. 

  • Area of thick undergrowth where animals hide. 

  • A hiding place. 

adj
  • Under coverture. 

  • Secret, surreptitious, concealed. 

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