U+0A21 Gurmukhi Letter Dda

The Wikipedia has the following information about this codepoint:

Gurmukhī (Punjabi: ਗੁਰਮੁਖੀ, Punjabi pronunciation: [ˈɡʊɾᵊmʊkʰiː], Shahmukhi: گُرمُکھی) is an abugida developed from the Laṇḍā scripts, standardized and used by the second Sikh guru, Guru Angad (1504–1552). Commonly regarded as a Sikh script, Gurmukhi is used in Punjab, India as the official script of the Punjabi language.

The primary scripture of Sikhism, the Guru Granth Sahib, is written in Gurmukhī, in various dialects and languages often subsumed under the generic title Sant Bhasha or saint language, in addition to other languages like Persian and various phases of Indo-Aryan languages.

Modern Gurmukhī has thirty-five original letters, hence its common alternative term paintī or "the thirty-five," plus six additional consonants, nine vowel diacritics, two diacritics for nasal sounds, one diacritic that geminates consonants and three subscript characters.