Area (surface unit)

An area or square decameter is a unit of area equal to 100 square meters. It was the surface unit implemented by the original decimal metric system. Its multiple is still frequently used: the hectare; and sometimes its submultiple: the centiare, which is equal to one square meter.

The International System of Units no longer includes this unit, since it takes the hectare as the base for agricultural areas. The International System of Units includes it, but only as a note.

The area is the surface of a square with sides 10 meters. If an area is divided into 100 equal parts; each of them is a centiare, or square meter.