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Ḍ - Wikipedia
Ḍ (minuscule: ḍ) is a letter of the Latin alphabet, formed from D with the addition of a dot diacritic. [1] In the transcription of Afro-Asiatic languages such as Arabic, ḍ represents an "emphatic" consonant [dˤ], and is used for that purpose in the Berber Latin alphabet. In the transcription of Indic and East Iranian languages, and in the orthography of the O'odham and Sicilian ...
D, or d, is the fourth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide.