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ألف خنجرية

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ـٰ • (-ā)

1. superscript alif, dagger alif (أَلِف خَنْجَرِيَّة (ʔalif ḵanjariyya)), indicates a long /aː/ where ا (ʔalif) is normally not written.

• ʔalif ḵanjariyya is a rare diacritic, is missing on standard keyboards and is sometimes replaced with a fatḥa ـَ (-a) in a vocalised Arabic text or omitted altogether, except in the Qur'an.
• ʔalif ḵanjariyya can be written with or without a fatḥa, e.g. with a fatḥa رَحْمَٰن (raḥmān) in the Middle East or without a fatḥa رَحْمٰن (raḥmān) in South Asia (Pakistan, India and Bangladesh)
• The word اللّٰه (allāh, “Allah”) is usually produced automatically by entering "alif + lām + lām + hāʾ" - ا ل ل ه (read from right to left). The word consists of ا (ʔalif) + ligature of doubled ل (lām) with a shadda ـّ and an ʔalif ḵanjariyya above ل (lām).
• In Wiktionary we use ʔalif ḵanjariyya to generate a correct transliteration ("ā") and to indicate a long /aː/. A fatḥa alone, without ʔalif ḵanjariyya or a long alif ا (ʔalif) would be transliterated as a short /a/.