What is "sanatani"

''An (otherwise unknown) author with the name Sānātanī is mentioned by Udayana (10th century).''

Sanātanī is a term often used by Indians to either describe denominations that adhere to Sanatana Dharma (Hinduism), or what is sometimes misunderstood to be Orthodox Hinduism. The term was popularized by Mahatma Gandhi in 1921.

The term Sanatani is used in contrast to 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).