Is “Tamasi” a name of Durga?
yes, in Devi-Maahatmya (Chapter 11, mantra 23), we get:
Medhe Saraswati Vare Bhuti Babravi Tamasi" meaning , O Devi,you are Medha, Saraswati, Varaniyaa, Parama-Aiswaryarupa, and Taamasi.
Is is a part of the famous hymn (Devyah stutih) sung by the devataas to praise Devi after Shumbha-badha.
Devi is Trigunatmika. In Sattwaguna, She becomes Sattwiki which is meant by the term Parama Aishwarya(Maha-Lakshmi),, In Rajoguna She becomes (Maha)Saraswati and in Tamo-Guna,She becomes Taamasi(Maha-Kali). She is called Turiya or Trigunaatita too in that book.
So "Taamasi' is used as a praise.
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