Ẓāʾ


', or ', is the seventeenth letter of the Arabic alphabet, one of the six letters not in the twenty-two akin to the Phoenician alphabet. In name and shape, it is a variant of. Its numerical value is 900. It is related to the Ancient North Arabian ?‎‎, and South Arabian script|South Arabian] ?.
ظَاءْ does not change its shape depending on its position in the word:

Frequency

is the rarest phoneme of the Arabic language. Out of 2,967 triliteral roots listed by Hans Wehr in his 1952 dictionary, only 42 contain ظ. is the least mentioned letter in the Quran, only being mentioned 853 times in the Quran.
In relation to other Semitic languages
In some reconstructions of Proto-Semitic phonology, there is an emphatic interdental fricative, /, featuring as the direct ancestor of Arabic, while it merged with in most other Semitic languages, although the South Arabian alphabet retained a symbol for.

Pronunciation

In Classical Arabic, it represents a velarized voiced dental fricative, and in Modern Standard Arabic, it represents an pharyngealized voiced dental but can also be a alveolar fricative for a number of speakers.
In most Arabic vernaculars ظ and ض ḍād merged quite early. The outcome depends on the dialect. In those varieties, where the dental fricatives and are merged with the dental stops and, ẓādʾ is pronounced or depending on the word; e.g. ظِل is pronounced but ظاهِر is pronounced, In loanwords from Classical Arabic is often, e.g. Egyptian ʿaẓīm "great".
In the varieties, where the dental fricatives are preserved, both and are pronounced. However, there are dialects in South Arabia and in Mauritania where both the letters are kept different but not consistently.
A "de-emphaticized" pronunciation of both letters in the form of the plain entered into other non-Arabic languages such as Persian, Urdu, Turkish. However, there do exist Arabic borrowings into Ibero-Romance languages as well as Hausa and Malay, where and are differentiated.
In English, the sound is sometimes represented by the digraph zh.
Notes:
  1. In Mauritania, ض is mostly pronounced as in , from ضحك, but generally appears in the lexemes borrowed from Standard Arabic as in , from * ضعيف.
  2. In Egypt, Lebanon, etc, ظ is mostly pronounced in inherited words as in , from ظلمة; , from عظم, but pronounced in borrowings from Literary Arabic as in ; from ظلم.
  3. In some accents in Egypt, the emphatic is pronounced as a plain.

    Character encodings