ozone vs song

ozone

noun
  • Fresh air, especially that breathed at the seaside and smelling of seaweed. 

  • An allotrope of oxygen (symbol O₃) having three atoms in the molecule instead of the usual two; it is a toxic gas, generated from oxygen by electrical discharge. 

  • Hypernym: greenhouse gas 

verb
  • To treat with ozone. 

song

noun
  • A melodious sound made by a bird, insect, whale or other animal. 

  • A low price, especially one under the expected value; chiefly in for a song. 

  • A musical composition with lyrics for voice or voices, performed by singing. 

  • An object of derision; a laughing stock. 

  • Poetical composition; poetry; verse. 

  • The distinctive sound that a male bird utters to attract a mate or to protect his territory; contrasts with call; also, similar vocalisations made by female birds. 

  • Any musical composition. 

  • The act or art of singing. 

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