Social justice is a philosophical, political, social, and legal movement in support of the rights of those who are marginalised, chiefly by poverty, but also (and increasingly) those who lack social privilege at any intersection.
Historically, it is a concept that has existed since ancient times. One of the earliest influential western writings on social justice was penned by Aristotle in Nicomachean Ethics volume V. This work discussed distributive justice. The term "social justice" itself was coined in the 1840s by a Jesuit priest named Luigi Taparelli. Partly due to its historical roots, the meaning of the phrase has been contentious. However in modern times, the consensus is that social justice has a secular definition:
Social justice involves creating a society based on principles of equality and solidarity, that understands and values human rights, and that recognises the dignity of every human being. At its 2007 World Summit for Social Development, the United Nations proclaimed 20 February as World Day of Social Justice. Governments pledged to promote the equitable distribution of income and greater access to resources through equity and equality and opportunity for all. The day aims to consolidate the efforts of the international community to eradicate poverty, and promote full employment and decent work, gender equity, rights of indigenous peoples and migrants, and access to social well-being and justice for all.