The Sanskrit word Sannyasin is used to define an individual who has taken initiation (Sannyas Diksha) into an Indian renunciate order by a qualified Sampradaya Guru. While details and rules related to Sannyasin initiation vary from sect to sect, two features remain consistent to all orders of Sannyasi: receiving the Sannyas Mantra from the Sampradaya Guru and renunciation of worldly aims and involvements.

In this ancient Indian spiritual pattern, initiation as a Sannyasin is intended as a socially recognized exemption from the mundane involvements of human life. The Sannyasin rejected worldly life to more fully embrace the spiritual path and patterns of approach as communicated by the Sampradaya Guru.

The explicit requirements for a Sannyasin of the Adi-Nath Sampradaya are:

• To renounce the world and take the Sannyas Mantra from the Sampradaya Guru.
• To not be married or live as a married person.
• To not be engaged in gainful employment.
• To not rent or own property.
• To not have dependents, male or female.
• To be of good and honest character.
• To understand spiritual life and its purpose.
• To always wear the outer cloth of a Sadhu.

The International Nath Order is not a Sannyas sect: no Sannyas initiation is ever bestowed in the International Nath Order.

References
Mahendranath, Shri Gurudev. Letter to Kapilnath (1989)