Mahdism is a concept in Islamic eschatology that refers to the belief in the appearance of the Mahdi, a messianic figure who is expected to restore justice and peace in the world. Synonyms for Mahdism include messianism, apocalypticism, and millenarianism, all of which describe religious and philosophical traditions that envision a monumental, transformative event in the future. Additionally, these words imply a deep spiritual longing for a better world, often characterized by suffering and injustice in the present. While Mahdism is specific to Islamic traditions, other religions have similar ideas of a future savior or a period of spiritual renewal.