A00034 - Quintar, Arabic Unit of Mass

The quintar, qintar, quintal or centner, from Latin centenarius ("hundredlike"), is a historical unit of mass in many countries which is usually defined as 100 base units of either pounds or kilograms. 

Both terms share their roots in the Classical Latin centenarius, meaning hundredlike, but the quintal has a convoluted etymology: It became Late Latin centenarium pondus, then in succession, Byzantine Greek κεντηνάριον (kentenarion) and Arabic qintar or quintar. The quintar was reimported to Europe by traders during the Middle Ages, where it became Medieval Latin quintale, and finally Old French quintal before passing into the English language from French.

The word centner, on the other hand, is simply a Germanicized form of its original Latin name centenarius.

Languages drawing its cognate name for the weight from Arabic qintar (quintar) include Spanish quintal, French quintal, Italian quintale, Portuguese quintal, Ukrainianквінтал (kvintal), Esperanto kvintalo. 

Languages taking their cognates from Germanicized centner include German Zentner, Lithuanian centneris, Swedish centner, Polish cetnar, Russian центнер (tsentner), Estonian tsentner, and Spanish centena.

Many European languages have come to translate both the Imperial and United States hundredweight as their cognate form of quintal or centner.

The concept has resulted in two different series of masses: Those based on the local pound (which after metrication was considered equivalent to half a kilogram), and those uprated to being based on the kilogram.

In Arab countries, the quintar was defined as be being about forty-five kilograms. 

In India and Albania, (kuintal), the quintal as equivalent to 100 kilogram was imported via Arabic influence and is a standard measurement of mass for agricultural products.

In France, the quintal used to be defined as 100 livres (pounds), about 48.95 kg, and has been redefined as 100 kg (mesures usuelles), and thus became the metric quintal with the symbol qq.

In Spain, the centena is still defined as 100 libras, or about 46 kg, but the metric quintal is also defined as 100 kg.

In Portugal, a quintal is 128 libras or about 58.75 kg.

The German Zentner is pound-based, and thus since metrication is defined as 50 kg, whereas the Austrian and Swiss Zentner since metrication has been re-defined as 100 kg.

Common agricultural units used in the Soviet Union were the 100-kilogram centner (центнер) and the term "centner per hectare". These are still used by countries that were part of the Soviet Union.

In Anglo-American countries, both terms quintal and centner were once alternative names for the hundredweight and thus defined either as 100 lb (exactly 45.359237 kg) or as 112 lb (about 50.84 kg).

The quintal was defined in the United States in 1866 as 100 kilograms. However, this is not in use and though it still appears in the statute, it has been declared obsolete by the NIST (the National Institute of Standards and Technology).