Rules of the Silent Noun (Nun Sakinah)
Clear Articulation (Ithhar)
Clear articulation occurs when the silent letter “n” or the tanween precedes one of the six letters of clear articulation, either in a single word or across two words. In this case, the letter is pronounced clearly without any nasalization, a process called clear articulation (Ithhar) or throat articulation, as the letters are articulated from the throat. The letters of clear articulation, in order from the furthest to the closest, are: Alif (ا), Ha (ه), Ain (ع), Ha (ح), Ghayn (غ), and Kha (خ). The rationale for articulating these letters clearly lies in their distance from the articulation point of the letter “n”.
Assimilation (Idgham)
Assimilation involves the merging of two letters; the first is a silent letter “n” and the second is a moving letter from the assimilation group, resulting in the pronunciation of a single, elongated sound. During articulation, one can notice a slight elevation of the tongue. The six letters of assimilation are: Ya (ي), Nun (ن), Meem (م), Waw (و), Lam (ل), and Ra (ر). For assimilation to occur, the letter “n” must meet the letter of assimilation across two separate words, with exceptions in the Quran found in “من راق” (min raaq) and “يس والقرآن” (Ya-Sin wal-Quran). Assimilation is further divided into two types: incomplete assimilation, with letters Ya, Nun, Meem, and Waw, where the “n” does not completely disappear but retains its nasalization; and complete assimilation, involving the letters Lam and Ra, where the “n” and its nasalization are entirely absorbed.
Conversion (Iqlaab)
Conversion involves transforming the letter “b” into a hidden “m” when it is preceded by the silent “n”. This process also results in a distinct nasalization. The justification for this conversion is to facilitate the pronunciation of “n,” making it easier to produce an “m” sound when the silent “n” is followed by the letter “b”.
Concealment (Ikhfa)
Concealment refers to the pronunciation of the silent “n” when it is situated between clear articulation and assimilation, followed by one of the letters of concealment. There are fifteen letters of concealment: Saad (ص), Thaal (ذ), Thaa (ث), Kaf (ك), Jeem (ج), Sheen (ش), Qaf (ق), Seen (س), Daal (د), Taa (ط), Zaa (ز), Faa (ف), Taa (ت), Dhaa (ض), and Zhaa (ظ). Concealment can appear within a single word or across two words and is categorized into three levels: high, middle, and low. The highest levels are with Taa, Daal, and Taa, while the lowest include Qaf and Kaf, with the remaining concealment letters falling in the middle range.