vulg. zı, The twentieth letter of the Turkish and Persian alphabets, and seventeenth of the Arabic. Its phonetic value is, according to Turkish pronunciation, that of a hard z. The full name of the letter is ظاء معجمە (the dotted ظ) and ظاء ضظغ (the ظ of the word ضظغ, in the ebjed formula).The ظ is one of the letters reduplicated in pronunciation instead of the ل of the Arabic definite article ال, when it follows this article as the initial letter of a noun.In Arabic derivation, the occurrence of ظ as the first radical of a triliteral root, such as ظلم, necessitates a modification of the servile ت of the eighth form (افتعال), which must then be.changed into ط or ظ; if the servile ت be changed into ظ; this latter combines with the first radical ظ as a reduplicated letter; thus, instead of اظتلام iztilâm, we have اظلام izzilâm, for اظطلام ; but if ط be used instead of the servile ت we may either use the word اظطلام iztilâm, or convert the radical ظ into a ط, and combine the two into one reduplicated ط; as, اطلام ittılâm. This last is of a less frequent occurrence.