Roman number vs decimal

Roman number

decimal

noun
  • A decimal place. 

  • A decimal point. 

  • The decimal system itself. 

  • A number expressed in the base-ten system, (particularly) a fractional numeral written in this system. 

adj
  • Concerning numbers expressed in decimal or mathematical calculations performed using decimal. 

verb
  • To represent with numbers after a decimal point. 

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