Definition: Provisional Government. Provisional government: is an emergency or interim government set up when no government has yet been established, or when a political void has been created by the collapse of an existing government.There is no specific way a provisional government must be organized or run.efinition: Provisional Government. Provisional government: is an emergency or interim government set up when no government has yet been established, or when a political void has been created by the collapse of an existing government.