pluralist

Concise Oxford English Dictionary © 2008 Oxford University Press:
pluralism/ˈplʊərəlɪzəm/

▶noun

• 1 a condition or system in which two or more states, groups, principles, etc. coexist.

  ■ a political theory or system of power-sharing among a number of political parties.

• 2 Philosophy a theory or system that recognizes more than one ultimate principle. Compare with monism.

• 3 the practice of holding more than one office or Church benefice at a time.

– derivatives
pluralist noun & adjective,
pluralistic adjective,
pluralistically adverb.