disc vs scurf

disc

noun
  • The flat surface of an organ, as a leaf, any flat, round growth. 

  • A vinyl phonograph / gramophone record. 

  • An intervertebral disc. 

  • Venus's disc cut off light from the Sun. 

  • Something resembling a disc. 

  • A thin, flat, circular plate or similar object. 

verb
  • To move towards, or operate at, zero blade pitch, orienting the propeller blades face-on to the oncoming airflow and maximising the drag generated by the propeller. 

  • To harrow with a disc harrow. 

scurf

noun
  • Minute membranous scales on the surface of some leaves, as in the goosefoot. 

  • A grey bull trout (Salvelinus confluentus). 

  • The foul remains of anything adherent. 

  • A skin disease. 

  • The flakes of skin that fall off as a result of a skin disease. 

  • Any crust-like formations on the skin, or in general. 

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