Dunam

A dunam (Ottoman Turkish, Arabic: دونم; dönüm; דונם), also known as a donum or dunum and as the old, Turkish, or Ottoman stremma, was the Ottoman unit of area equivalent to the Greek stremma or English acre, representing the amount of land that could be ploughed by a team of oxen in a day. The legal definition was "forty standard paces in length and breadth", but its actual area varied considerably from place to place, from a little more than 900 m2 in Ottoman Palestine to around 2,500 m2 in Iraq.

The unit is still in use in many areas previously ruled by the Ottomans, although the new or metric dunam has been redefined as exactly one decare (1,000 m2), which is 1/10 hectare (1/10 × 10,000 m2), like the modern Greek royal stremma.

History
The name dönüm, from the Ottoman Turkish dönmek (دونمك, "to turn"), appears to be a calque of the Byzantine Greek stremma and had the same size. It was likely adopted by the Ottomans from the Byzantines in Mysia-Bithynia.

The Dictionary of Modern Greek defines the old Ottoman stremma as approximately 1,270 m2, but Costas Lapavitsas used the value of 1,600 m2 for the region of Naoussa in the early 20th century.

Albania, Bosnia and Herzegovina, Serbia, Montenegro
In Bosnia and Herzegovina and also Serbia, the unit is called dulum (дулум) or dunum (дунум). In Bosnia and Herzegovina dunum (or dulum) equals 1,000 m2. In the region of Leskovac, south Serbia, One dulum is equal to 1,600 m2. In Albania it is called dynym or dylym. It is equal to 1,000 m2.

Bulgaria
In Bulgaria, the decare (декар) is used, which is an SI unit, literally meaning 10 ares.

Cyprus
In Cyprus, a donum is $1,337.804 m2$ or 14400 square feet. In the Republic of Cyprus older Greek-Cypriots also still refer to the donum using the local Greek Cypriot dialect word σκάλες [skales], rather than the mainland Greek word stremma (equivalent to a decare). However, since 1986 officially Cyprus uses the square metre and the hectare.

A donum consists of 4 evleks, each of which consists of $334.451 m2$ or 3.600 square feet.

Greece
In Greece, the old dönüm is called a "Turkish stremma", while today, a stremma or "royal stremma" is exactly one decare, like the metric dönüm.

Iraq
In Iraq, the dunam is 2500 m2.

Israel and Turkey
In Israel and Turkey, the dunam is 1000 m2, which is 1 decare. From the Ottoman period and through the early years of the British Mandate for Palestine, the size of a dunam was 919.3 m2, but in 1928, the metric dunam of 1000 m2 was adopted, and this is still used today in Israel.

United Arab Emirates
The Dubai Statistics Center and Statistics Centre Abu Dhabi use the metric dunam (spelt as donum) for data relating to agricultural land use. One donum equals 1,000 m2.

Variations
Other countries using a dunam of some size include Libya and Syria.

Conversions
A metric dunam is equal to:


 * 1,000 square metres (exactly)
 * 10 ares (exactly)
 * 1 decare (exactly)
 * 0.1 hectares (exactly)
 * 0.001 square kilometres (exactly)
 * 0.247105381 acres (approx)
 * 1,195.99005 square yards (approx)
 * 10,763.9104 square feet (approx)

Comparable measures
The Byzantine Greek stremma was the probable source of the Turkish unit. The zeugarion (Turkish çift) was a similar unit derived from the area plowed by a team of oxen in a day. The English acre was originally similar to both units in principle, although it developed separately.