rust vs saffron

rust

noun
  • A reddish-brown color. 

  • A similar substance based on another metal (usually with qualification, such as "copper rust"). 

  • A disease of plants caused by a reddish-brown fungus. 

  • Damage caused to stamps and album pages by a fungal infection. 

  • The deteriorated state of iron or steel as a result of moisture and oxidation. 

verb
  • To (cause to) degenerate in idleness; to make or become dull or impaired by inaction. 

  • To oxidize, especially of iron or steel. 

  • To cause to oxidize. 

  • To be affected with the parasitic fungus called rust. 

  • Of a black cat or its fur, to turn rust-coloured following long periods of exposure to sunlight. 

saffron

noun
  • An orange-yellow colour, the colour of a lion's pelt. 

  • A spice (seasoning) and colouring agent made from the stigma and part of the style of the plant, sometimes or formerly also used as a dye and insect repellent. 

  • The plant Crocus sativus, a crocus. 

adj
  • Having an orange-yellow colour. 

verb
  • To add saffron to (a food), for taste, colour etc. 

  • To dye (a fabric, garment, etc.) with a saffron-based dye. 

  • To give a saffron colour to (something). 

  • To colour (a metal or wooden surface) with a gilding product containing saffron. 

  • To embellish. 

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