Significance of Matri
Matri, in the contexts of Vaishnavism and Purana, signifies 'mother' and encompasses various aspects of divine maternal figures. It represents affectionate relationships within devotional service and refers to divine mothers seeking refuge in Goddess Durga for protection. Matri includes eight deities acting as spiritual maternal figures, and a collective group of divine mothers associated with nurturing, guidance, and protection. Moreover, in Shaktism, Matri represents the seven mother goddesses worshiped during Durgapuja, highlighting their significance in Hindu rituals.1
The below excerpts are indicatory and do represent direct quotations or translations. It is your responsibility to fact check each reference.
Hindu concept of 'Matri'
Matri in Hinduism encompasses divine mothers and goddesses, symbolizing nurturing, protection, and fearlessness. Represented in worship, they aid devotees through blessings, embody maternal qualities, and partake in spiritual battles against negative forces.
Vaishnavism
Books
From: Brihad Bhagavatamrita (commentary)
(1) Matri refers to the term used for 'mother,' addressed in the context of Shri Parikshit's speech.[1]
From: Bhakti-rasamrta-sindhu
(1) Refers to a state of affectionate and friendly relationships within the context of devotional service.[2]
Plural form: Matris.