The Republic of India has two principal official short names, each of which is historically significant: India and Bharat. A third name, Hindustan, is also used commonly when Indians speak among themselves. The usage of "Bhārat", "Hindustān", or "India" depends on the context and language of conversation.
The name "India" is originally derived from the name of the river Sindhu (Indus River) and has been in use in Greek since Herodotus (5th century BCE). The term appeared in Old English by the 9th century and reemerged in Modern English in the 17th century.
"Bhārat" gained popularity in India during the nineteenth century. It is the shortened form of the term "Bhāratavarṣa" which is extensively used in the literature of the native religions. "Bhāratavarṣa" is derived from the name of the Vedic tribe of Bharatas who are mentioned in the Rigveda as one of the principal peoples of Aryavarta (Land of the Aryans). At first the name Bhāratavarṣa referred only to the western part of the Gangetic Valley,[1][2] but was later[when?] more broadly applied to the Indian subcontinent.[citation needed] In 1949, it was adopted as an official name for the Republic of India by the Constituent Assembly along with "India".
"Hindustān" is another common name for the Republic of India and is also derived from the name of the river Sindhu. It gained popularity in India in the 11th century in Islamic literature and became the common name for the northern Indian subcontinent in Indian languages, though it has been in Persian usage since at least the 3rd century CE while its earlier form "Hindush" was used as early as 6th century BCE. The term 'Hindu' was the Old Persian adaption of "Sindhu". "Hindustan" is still commonly used in the subcontinent to refer to the modern day Republic of India by Hindustani speakers.