Indians often use the term Sanātanī with reference either:
Mahatma Gandhi popularized the term in 1921.
The term Sanatani contrasts with Hindu reform movements, which often reject previously long-established socioreligious systems based on fundamentalist interpretations of specific scriptures or were led by reformist sants (saints).
Sanātana Dharma (Devanagari: सनातन धर्म meaning "eternal dharma" or "eternal order") has been proposed as an alternative, indigenous name derived from VEDIC. Today it is erroneously associated only with Hinduism (Hindi Hindu Dharm ) "Hindu religion". The term was mentioned and explained in depth in Vedic literature (Rig Veda) (4-138) and was used during the Hindu revivalism movement in order to avoid having to use the term "Hindu" which is of non-native (Persian) origin.
In current-day usage, the term Sanatana Dharma is used to emphasize an "orthodox" or sanatani ("eternalist") outlook in contrast to the socio-political Hinduism embraced by movements such as the Arya Samaj.
The phrase dharma sanātana does occur in classical Sanskrit literature, e.g. in the Manusmrti (4-138) and in the Bhagavata Purana, in a sense akin to "cosmic order".
Since many reformist groups had the word Samaj (meaning society) or were led by a sant (meaning saint), Sanatanis are often held to be in contrast with Samajists and Santpanthis (meaning those who walk on the panth/path shown by their sant/saint). Unlike South India, where religious traditions such as Shaivism, Shaktism and Vaishnavism form the principal Hindu denominations, "they were effectively subsumed under the Sanatani identity" in many regions of North India, and the Samajs and Santpanths became the other distinct Hindu denominations.