Yogindra Mohini Biswas or Yogin Ma ( Bengali: যোগীন মা) as she was popularly called, was a foremost woman disciple of Sri Sarada Devi, holy mother of the Ramakrishna order and the spiritual consort of Sri Ramakrishna. Together with Golap Ma, she was a constant companion of Sri Sarada Devi and a major witness and an active contributor to the early formation of the monastic order of Sri Ramakrishna. She stayed with the holy mother in the Udbodhan House in Calcutta, which was built by Swami Saradananda for the use of Sri Sarada Devi.
Yogin Ma was born in Calcutta on January 16, 1851 to Prasanna Kumar Mitra, a successful physician. She was given in marriage to Ambika Charan Biswas at the age of six or seven, as it was the prevailing custom in Bengal to marry off girls at an early age. Her husband squandered all his wealth and despite her best attempts of rehabilitating and reforming him, became a habitual drunkard. Yogin Ma finally left her husband's place with her only daughter and took shelter with her widowed mother in her father's house in Bagbazar area of Calcutta.
Adversity propelled her to develop intense yearning for God Realization and a chance encounter with Sri Ramakrishna, the 19th century mystic saint of Bengal, changed her life. In 1883, Yogin Ma first met Sri Ramakrishna in the house of Balaram Bose, who was a great devotee. After a few meetings in Dakshineswar, Sri Ramakrishna initiated her and became her Guru and mentor. Yogin Ma first met Sarada Devi in Dakshineswar, in the building of Nahabat, where the holy mother stayed. By staing as a close companion of the holy mother Yogin Ma had recorded and shared some of her day to day experiences which serves as an important testimony to the early life and the spiritual practices of Sri Sarada Devi during her stay in Dakshineswar. She recounted many incidents of her life during this period - her travels to Vrindavan after Sri Ramakrishna's demise, her travels to Puri and stay in Calcutta in several of her devotees' house, including that of Balaram Bose. Life lived by Sri Ramakrishna and the holy mother inspired Yogin Ma to practise spiritual disciplines, and lead a holy and pure life like a nun. She also studied the scriptures, esp. the Ramayana and Mahabharata and the Puranas. Thus later in her life she was able to help Sister Nivedita in writing one of her famous books, "The Cradle Tales of Hinduism" . Sri Ramakrishna had acknowledged her spiritual prowess by predicting that, "She is not an ordinary flower that will blossom quickly, she is a thousand-petalled lotus that will open slowly."  When Sri Ramakrishna died on 16 August 1886, Yogin Ma was in Vrindaban. There she was joined by Sri Sarada Devi of whom she later became a lifelong companion. The mother used to call her "Meye Yogen" or "lady Yogen", for distinguishing her from Swami Yogananda, who was also known as "Yogen". Her daughter Ganu died and she was left with three grandsons who were brought up under the tutelage of Swami Saradananda, and at least one of them later joined the order and was initiated by Sri Sarada Devi.
Yogin-ma was a woman of strong determination. Whatever she undertook she carried through to perfection. Yogin-ma looked on the monastic disciples as her own children and they, including Swami Vivekananda in turn were very free with her. She was an expert cook and Swami Vivekananda often requested her to prepare a meal for him. The American disciple of Swami Paramananda, sister Devmata recollects about her, "Yogin-ma always seemed to me one of the noblest of Sri Ramakrishna's disciples… She did not abandon her householder life, but no nun in a cloister was more rigid in her spiritual observance than she… No service was ever omitted, no care neglected." Her life was very austere and she accompanied the holy mother in performing the 'Austerity of the Five Fires', considered as a very sacred and dangerous ritual.
She later came back to Calcutta along with the holy mother and often stayed with her in Udbodhan House in Calcutta. Toward the end of her life, Yogin Ma took the final monastic vows according to the Vedic tradition from Swami Saradananda. Swami Premananda or Baburam Maharaj was also present at the ceremony. She died on June 4, 1924, at the Udbodhan House, at the age of seventy-three.
- A Holy Woman of modern India by Swami Asheshananda Archived July 28, 2011, at the Wayback Machine.
- Recordings of Yogin Ma Archived March 24, 2012, at the Wayback Machine.
- "Women Saints of East and West", by Swami Ghanananda, John Stewart-Wallace, 1979, Vedanta Press, Hollywood, California
- Yogin Ma, RKM Nagpur
- Women disciples of Ramakrishna