He became a sannyasin on 31 December 1975 and received the name Swami Vinod Bharti.
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By the way, sannyasi is in Merriam-Webster, but sannyas and sannyasin seem not to be.
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His mother took up the life of a sannyasin, and Sri Ramana began to give her intense, personal instruction, while she took charge of the Ashram kitchen.
From the en.wikipedia.org
He became a sannyasin in the mid-1970s, but later left the movement and instead found spiritual companionship and guidance with U.G. Krishnamurti, whose biography he wrote in 1992.
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A Hindu religious mendicant
Sannyasa (sau1E43nyu0101sa) is the life stage of renunciation within the Hindu philosophy of four age-based life stages known as ashramas, with the first three being Brahmacharya (bachelor student), Grihastha (householder) and Vanaprastha (forest dweller, retired)...
One who has renounced the world in seek of self-realization.
A man in the renounced order, the final stage of spiritual progress in the varnashrama system. Sannyasis take a vow of lifetime celibacy.
An ascetic, one who belongs to the fourth stage of life