The word "Hindu" is an exonym. This word "Hindu" is derived from the Indo-Aryan and Sanskrit word "Sindhu", which means "a large body of water", covering "river, ocean". It was used as the name of the Indus River and also referred to its tributaries. The actual term " first occurs, states Gavin Flood, as "a Persian geographical term for the people who lived beyond the river Indus (Sanskrit: "Sindhu")", more specifically in the 6th-century BCE inscription of Darius I. The Punjab region, called Sapta Sindhu in the Vedas, is called "Hapta Hindu" in Zend Avesta. The 6th-century BCE inscription of Darius I mentions the province of "Hidush", referring to northwestern India. The people of India were referred to as "Hinduvān" (Hindus) and "hindavī" was used as the adjective for Indian in the 8th century text "Chachnama". The term 'Hindu' in these ancient records is an ethno-geographical term and did not refer to a religion. The Arabic equivalent "Al-Hind" likewise referred to the country of India.