What is the meaning of ض?

Arabic letter ḍād

The fifteenth letter of the Arabic alphabet. It is preceded by ص () and followed by ط ().

The twenty-sixth letter in traditional abjad order, which is used in place of numerals for list numbering (abjad numerals). It is preceded by ذ () and followed by ظ ().

The twenty-eighth letter of the Balti alphabet, written in the Perso-Arabic script

The twenty-eighth letter of the Burushaski alphabet, written in the Perso-Arabic script

The fifteenth letter of the Arabic alphabet. It is preceded by ص (ṣād) and followed by ط (ṭāʔ).

The twenty-eighth letter of the Khowar abjad.

The twentieth letter of the Xiao'erjing abjad

The twenty-sixth letter of the traditional alphabet chart of Kashmiri.

The sixteenth letter of the Malay alphabet, written in the Arabic script.

The twenty-fifth letter of the Pashto alphabet.

The eighteenth letter of the Perso-Arabic alphabet. It is preceded by ص and followed by ط. Its name is ضاد (zâd), In Dari it may also go by the names ضوات (zwât) and ضواد (zwâd, zwâd).

The twenty-first letter of Punjabi in the Shahmukhi script.

The thirty-second letter of the Sindhi abjad.

The twenty-first letter of the Urdu abjad.

Source: wiktionary.org