Hindu :: Hindu (n.) A native inhabitant of Hindostan. As an ethnical term it is confined to the Dravidian and Aryan races; as a religious name it is restricted to followers of the Veda.
Hindustani :: Hindustani (a.) Of or pertaining to the Hindoos or their language.
Hindustani :: Hindustani (n.) The language of Hindostan; the name given by Europeans to the most generally spoken of the modern Aryan languages of India. It is Hindi with the addition of Persian and Arabic words.