The Mother
The Mother is a term used in the the Integral Yoga of Sri Aurobindo. It simultaneously refers both to the formative aspect of Divine Consciousness (i.e. shakti/शक्ति) and Mirra Alfassa (21 February 1878 – 17 November 1973), an individual who functioned as an Earthly channel/expression of the supreme formative (mahashzakti/महाशक्ति) aspect of Consciousness.
Notes
Sri Aurobindo characterizes mahashakti/महाशक्ति as the Divine Mother. In the New Age movement महाशक्ति is depersonalized to be the sacred feminine. In Chinese philosophy mahashakti is yin. On the Lightning Path, mahashakti is characterized as the formative principle of Consciousness (BOLIFE).
Sri Aurobindo notes that the goal of spiritual is to fully express mahashakti. "The last stage of this perfection will come when you are completely identified with the Divine Mother and feel yourself to be no longer another and seperate being...but truly a child and eternal portin of her consciousness and force." (Aurobindo, 2013: 25).
Further Reading
Mirra Alfassa https://en.wikipedia.org/wiki/Mirra_Alfassa
Aurobindo, Sri (2013). The Mother Pondicherry: Sri Aurobindo Trust