(abbreviated `ha') a unit of surface area equal to 100 ares (or 10,000 square meters)
"The real estate agent explained that the entire vineyard spans exactly fifty hectares."
A unit of surface area (symbol ha) equal to 100 ares (that is, 10,000 square metres, one hundredth of a square kilometre, or approximately 2.5 acres), used for measuring the areas of geographical features such as land and bodies of water.
"The new solar farm will cover exactly fifty hectares of flat desert land near the town border."