national anthem vs song

national anthem

noun
  • The official song of a constituent state of a country. 

  • The official song of a nation or sovereign state, generally of a patriotic nature and played at events to celebrate or honor said state. 

song

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

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

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

  • 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 national anthem and song occurred in a corpus of books? (source: Google Ngram Viewer )