o vs y

o

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

noun
  • A zero (used in reading out numbers). 

  • Operator 

  • The name of the Latin-script letter O/o. 

  • Object, see SVO 

adj
  • Over 

y

character
  • The twenty-fifth letter of the English alphabet, called wy or wye and written in the Latin script. 

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