Aboriginal vs American Indian

Aboriginal

adj
  • Of or pertaining to Australian Aboriginal peoples, Aborigines, or their language. 

name
  • Any of the native languages spoken by Australian aborigines. 

noun
  • An Aboriginal inhabitant of Australia. 

American Indian

adj
  • Relating to the indigenous peoples of the Americas or their languages. 

noun
  • A member of some indigenous peoples of the Americas, especially the United States, but excluding the Inuit, Yupik, and Aleuts. 

  • An indigenous person from the United States. 

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