Citizens, by definition, are the participatory members of a particular nation who enjoy some rights by adhering to set standards and laws of the government. They must be 'willfully' concerned to defend the State and make it better in all possible ways. Taking a cue from that, the idea of global citizenship must entail roles and responsibilities for global issues as terrorism, global warming, trafficking, civil war, genocide, and the like. As far as the definition of global citizenship is concerned, it must include the rights and responsibilities of people towards the environment, society, and the world as a whole.
A global citizen must be a proactive contributor in dealing with global challenges with an aim to make the world more secure, tolerant, and inclusive. The idea of global citizenship automatically places a person beyond his national identities. It means that individuals will rise above their specific interests to make a positive contribution in all possible ways. At the national level, it would mean a sharp reduction in issues arising out of the hegemony of some specific countries. More so, the idea expects that social injustice will take a beating as participants will work towards making the world more sustainable and equitable in the future. As a matter of 'Right', global citizens will be entitled to the protection of their basic rights irrespective of the nation or State they belong to. This, including some other rights as equal protection, recognition, and non-discrimination, are already included in the Universal Declaration of Human Rights.
Furthermore, the concept of the global citizenship must establish clear and concise differences between the national citizenship and the world citizenship. It must explain that the term transcends any particular geographical boundaries and narrow attachments thereof. It is, rather, a perception that aims to engage with the environment, and the whole world. To waive off the confusions, the definition must, explicitly, point out that a person can be a world citizen while upholding the citizenship for a particular nation. Though he/she does not need to denounce the national citizenship, it is duly expected that the global concerns will always come first, and local identities will take the second place.
In the narrow sense, some of the aspects of global citizenship and national citizen seem in conflict with each other. For instance, individuals to two warring nations will automatically negate the ideas of mutual respect and recognition. Kant, a famous deontologist, has mentioned that these two concepts are not antithesis, but complementary. A brief mention of the related Philosophical ideologies will make the understanding more clear and holistic.
Last but not the least, the definition must include the approach towards the 'global citizenship' as it is only an ethos, not any additional subject to be studied and crammed. It is a novel way of thinking. As scholars aver, a whole-school approach involving the learner and the communities can impart a good understanding of global citizenship. Helping the people learn this approach will assist them to practice it in better and constructive manner.
References
Faulks, K. (2000). Citizenship. Psychology Press.
Miller, D. (2011). The Idea of Global Citizenship. Retrieved July 3, 2016, from www.nuffield.com: https://www.nuffield.ox.ac.uk/politics/papers/2011/David%20Miller_working%20paper%202011_02.pdf
Sweet, W. (2003). Philosophical Theory and The Universal Declaration of Human Rights. University of Ottawa Press.