Definition of Hectare

A hectare (symbol ha) is a metric unit of surface area, equal to 100 ares (the name is a contraction of the SI prefix hecto + are). It is a non-SI unit currently accepted (although discouraged) for use with the SI. Its use is widespread in agriculture where it is more practical than either square metres or square kilometres, typical fields being a few hectares in size.

In India, also the abbreviation hac is used.