hectare [HEHK-tahr]

from

Abbreviated as ha, a hectare is a unit of surface or land equivalent to 10,000 square meters or 2.471 acres. In countries using the metric system—such as Europe and South America—vineyard area is expressed in hectares. A European vineyard with 50 hectares is equivalent to a U.S. vineyard with just over 123 acres; a 250-acre U.S. vineyard is tantamount to about a 101-hectare European vineyard.