What is the meaning of خ?

The eighth letter of the Acehnese alphabet, written in the Arabic script.

The seventh letter of the Arabic alphabet, called خَاء (ḵāʔ) and written in the Arabic script; preceded by ح (ḥ) and followed by د (d).

The twenty-fourth numeral symbol of the Arabic alphabet (traditional abjad order, used for list numbering), written in the Arabic script; preceded by ث (ṯ) and followed by ذ (ḏ).

The twelfth letter of the Balti alphabet, written in the Arabic script.

The fourteenth letter of the Burushaski alphabet, written in the Arabic script.

The seventh letter of the Hijazi Arabic alphabet, called خَاء (ḵāʔ) and written in the Arabic script; preceded by ح (ḥāʔ) and followed by د (dāl).

The tenth letter of the Khowar alphabet, written in the Arabic script; preceded by ح and followed by ݯ.

The tenth letter of the Pahari-Potwari alphabet, written in the Shahmukhi script; preceded by ح (ḥe) and followed by د (dāl).

The tenth letter of the Xiao'erjing abjad, written in the Arabic script.

The fourteenth letter of the Kashmiri alphabet, written in the Arabic script; preceded by ح and followed by د.

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

The twelfth letter of the Pashto alphabet, written in the Arabic script; preceded by ح and followed by د.

The ninth letter of the Persian alphabet, written in the Arabic script; preceded by ح and followed by د.

The tenth letter of the Punjabi alphabet, written in the Shahmukhi script; preceded by ح (ḥe) and followed by د (dāl).

The eighteenth letter of the Sindhi alphabet, written in the Arabic script; preceded by ح and followed by د.

The tenth letter of the Urdu alphabet, written in the Arabic script; preceded by ح and followed by د.

The eighth letter of the Uyghur alphabet, written in the Arabic script; preceded by چ and followed by د.

Source: wiktionary.org