u vs uranium

u

noun
  • A thing in the shape of the letter U 

  • The name of the Latin-script letter U/u. 

pron
  • you (in text messaging and internet conversations) 

character
  • The twenty-first letter of the English alphabet, called u and written in the Latin script. 

uranium

noun
  • The element with atomic number 92 and symbol U: a radioactive silvery-grey metal in the actinide series. 

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