arcdegree vs fingerbreadth

arcdegree

noun
  • A unit of measurement of angle equal to ¹⁄₃₆₀ of a circle's circumference. 

fingerbreadth

noun
  • A (usually approximate and informal) unit of measurement based upon the radial width of the human finger. 

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