Editing Cubit (section)

==Islamic world==
In the Islamic world, the cubit ({{transliteration|ar|dhirāʿ}}) had a similar origin, being originally defined as the arm from the elbow to the tip of the middle finger.<ref name="EI2">{{EI2 | last = Hinz | first = W. | title = Dhirāʿ | volume = 2 | pages = 231–232}}</ref> Several different cubit lengths were current in the medieval Islamic world for the unit of length, ranging from {{convert|48.25-145.6|cm|in|abbr=on|frac=32}}, and in turn the {{transliteration|ar|dhirāʿ}} was commonly subdivided into six handsbreadths ({{transliteration|ar|qabḍa}}), and each handsbreadth into four fingerbreadths ({{transliteration|ar|aṣbaʿ}}).<ref name="EI2"/> The most commonly used definitions were:
* the '''legal cubit''' ({{transliteration|ar|al-dhirāʿ al-sharʿiyya}}), also known as the hand cubit ({{transliteration|ar|al-dhirāʿ al-yad}}), cubit of Yusuf ({{transliteration|ar|al-dhirāʿ al-Yūsufiyya}}, named after the 8th-century {{transliteration|ar|[[qadi|qāḍī]]}} Abu Yusuf), postal cubit ({{transliteration|ar|al-dhirāʿ [[al-barid|al-barīd]]}}), "freed" cubit ({{transliteration|ar|al-dhirāʿ al-mursala}}) and thread cubit ({{transliteration|ar|al-dhirāʿ al-ghazl}}). It measured {{convert|49.8|cm|in|frac=16|abbr=on}}, although in the [[Abbasid Caliphate]] it measured {{convert|48.25|cm|in|frac=16|abbr=on}}, possibly as a result of reforms of Caliph [[al-Ma'mun]] ({{reign|813|833}}).<ref name="EI2"/>
* the '''black cubit''' ({{transliteration|ar|al-dhirāʿ al-sawdāʾ}}), adopted in the Abbasid period and fixed by the measure used in the [[Nilometer]] on [[Rawda Island]] at {{convert|54.04|cm|in|frac=16|abbr=on}}. It is also known as the common cubit ({{transliteration|ar|al-dhirāʿ al-ʿāmma}}), sack-cloth cubit ({{transliteration|ar|al-dhirāʿ al-kirbās}}), and was the most commonly used in the [[Maghreb]] and [[Islamic Spain]] under the name {{transliteration|ar|al-dhirāʿ al-Rashshāshiyya}}.<ref name="EI2"/>
* the '''king's cubit''' ({{transliteration|ar|al-dhirāʿ [[al-malik]]}}), inherited from the [[Sassanid Persia]]ns. It measured eight {{transliteration|ar|qabḍa}} for a total of {{convert|66.5|cm|in|frac=16|abbr=on}} on average. It was this measure used by [[Ziyad ibn Abihi]] for his survey of [[Iraq (region)|Iraq]], and is hence also known as Ziyadi cubit ({{transliteration|ar|al-dhirāʿ al-Ziyādiyya}}) or survey cubit ({{transliteration|ar|al-dhirāʿ al-misāḥaʾ}}). From Caliph [[al-Mansur]] ({{reign|754|775}}) it was also known as the [[Hashemite]] cubit ({{transliteration|ar|al-dhirāʿ al-Hāshimiyya}}). Other identical measures were the work cubit ({{transliteration|ar|al-dhirāʿ al-ʿamal}}) and likely also the {{transliteration|ar|al-dhirāʿ al-hindāsa}}, which measures {{convert|65.6|cm|in|frac=16|abbr=on}}.<ref name="EI2"/>
* the '''cloth cubit''', which fluctuated widely according to region: the Egyptian cubit ({{transliteration|ar|al-dhirāʿ al-bazz}} or {{transliteration|ar|al-dhirāʿ al-baladiyya}}) measured {{convert|58.15|cm|in|frac=32|abbr=on}}, that of [[Damascus]] {{convert|63|cm|in|frac=2|abbr=on}}, that of [[Aleppo]] {{convert|67.7|cm|in|frac=16|abbr=on}}, that of [[Baghdad]] {{convert|82.9|cm|in|frac=16|abbr=on}}, and that of [[Istanbul]] {{convert|68.6|cm|in|frac=16|abbr=on}}.<ref name="EI2"/>

A variety of more local or specific cubit measures were developed over time: the "small" Hashemite cubit of {{convert|60.05|cm|in|frac=32|abbr=on}}, also known as the cubit of Bilal ({{transliteration|ar|al-dhirāʿ al-Bilāliyya}}, named after the 8th-century [[Basra]]n {{transliteration|ar|qāḍī}} Bilal ibn Abi Burda); the Egyptian carpenter's cubit ({{transliteration|ar|al-dhirāʿ bi'l-najjāri}}) or architect's cubit ({{transliteration|ar|al-dhirāʿ al-miʿmāriyya}}) of {{circa|{{convert|77.5|cm|in|frac=16|abbr=on}}}}, reduced and standardized to {{convert|75|cm|in|frac=2|abbr=on}} in the 19th century; the house cubit ({{transliteration|ar|al-dhirāʿ al-dār}}) of {{convert|50.3|cm|in|frac=16|abbr=on}}, introduced by the Abbasid-era {{transliteration|ar|qāḍī}} Ibn Abi Layla; the cubit of Umar ({{transliteration|ar|al-dhirāʿ al-ʿUmariyya}}) of {{convert|72.8|cm|in}} and its double, the scale cubit ({{transliteration|ar|al-dhirāʿ al-mīzāniyya}}) established by al-Ma'mun and used mainly for measuring canals.<ref name="EI2"/>

In medieval and early modern Persia, the cubit (usually known as {{transliteration|ar|gaz}}) was either the legal cubit of {{cvt|49.8|cm|in|frac=16}}, or the [[Isfahan]] cubit of {{convert|79.8|cm|in|frac=16|abbr=on}}.<ref name="EI2"/> A royal cubit ({{transliteration|ar|gaz-i shāhī}}) appeared in the 17th century with {{convert|95|cm|in|frac=2|abbr=on}}, while a "shortened" cubit ({{transliteration|ar|gaz-i mukassar}}) of {{convert|6.8|cm|in|frac=16|abbr=on}} (likely derived from the widely used cloth cubit of Aleppo) was used for cloth.<ref name="EI2"/> The measure survived into the 20th century, with 1 {{transliteration|ar|gaz}} equal to {{convert|104|cm|in|frac=2|abbr=on}}.<ref name="EI2"/> [[Mughal India]] also had its own royal cubit ({{transliteration|ar|dhirāʿ-i pādishāhī}}) of {{convert|81.3|cm|in|frac=16|abbr=on}}.<ref name="EI2"/>