Siddhaṃ, also known in its later evolved form as Siddhamātṛkā, is a medieval Brahmic abugida, derived from the Gupta script and ancestral to the Nāgarī, Eastern Nagari, Tirhuta, Odia and Nepalese scripts.

The Brahmic scripts, also known as Indic scripts, are a family of abugida writing systems. They are used throughout the Indian subcontinent, Southeast Asia and parts of East Asia. They are descended from the Brahmi script of ancient India and are used by various languages in several language families in South, East and Southeast Asia: Indo-Aryan, Dravidian, Tibeto-Burman, Mongolic, Austroasiatic, Austronesian, and Tai. They were also the source of the dictionary order (gojūon) of Japanese kana.