The term “New World Order” has two meanings. The original, benign meaning is a period of history evidencing a dramatic change in world political thought and balance of power. It refers to periods like after the First World War, the Second World War, and the fall of communism.
The second meaning is the one used by conspiracy theorists. In this case, “New World Order” means a secretive power elite with a globalist agenda conspiring to eventually rule the world through an authoritarian one-world government. This second meaning is just a conspiracy theory, which is not an actual fact but believed as true anyway by its adherents.