confederacy vs symbiosis

confederacy

noun
  • Specifically, an instance of a decentralized governing structure among the indigenous peoples of North America. 

  • A state where the sovereign constituent units delegate their authority to the centre. As opposed to a federation, where the central and regional governments are each equal and sovereign in their own sphere. 

  • An alliance. 

symbiosis

noun
  • The state of people of different types, races, cultures, communities, etc., living together. 

  • The occurrence of two different or opposing things in the same time and place. 

  • A close, prolonged association between two or more organisms of different species, regardless of benefit to the members. 

  • A close, prolonged association between two or more organisms of different species that normally benefits both members. An interspecies cooperation. 

  • A relationship of mutual benefit, especially among different species. 

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