m vs o

m

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

verb
  • make 

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 

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