diadem vs festoon

diadem

verb
  • To adorn with a diadem; to crown. 

noun
  • Regal power; sovereignty; empire—considered as symbolized by the crown. 

  • A crown. 

  • An ornamental headband worn as a badge of royalty. 

  • An arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its centre. 

festoon

verb
  • To decorate with ornaments, such as garlands or chains, which hang loosely from two tacked spots. 

  • To decorate or bedeck abundantly. 

  • To apply texturing to (a denture) to simulate human tissue. 

  • To make festoons. 

noun
  • Texturing applied to a denture to simulate human tissue. 

  • Any of a series of wrinkles on the backs of some ticks. 

  • A cloud on Jupiter that hangs out of its home belt or zone into an adjacent area forming a curved finger-like image or a complete loop back to its home belt or zone. 

  • A specific style of electric light bulb consisting of a cylindrical enclosure with two points of contact on either end providing power to the filament or diode. 

  • An ornament such as a garland or chain which hangs loosely from two tacked spots. 

  • Two sets of rollers used to create a buffer of material on web handling equipment. 

  • A bas-relief, painting, or structural motif resembling such an ornament. 

  • A raised cable with light globes attached. 

  • Any of various papilionid butterflies of the genus Zerynthia. 

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