d vs i

d

character
  • The fourth letter of the English alphabet, called dee and written in the Latin script. 

prefix
  • the prefix dis- or des- 

symbol
  • a British penny; an old penny (the modern decimal penny being abbreviated p). 

  • Die or dice 

  • penny, a measure of the size of nails 

i

character
  • The ninth letter of the English alphabet, called i and written in the Latin script. 

noun
  • The name of the Latin-script letter I/i. 

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