area unit
acre
"An area unit which is equivalent to 1 furlong x 1 chain. This is equal to an area of 4,046.856,4224 square meters, or 43,500 square feet." [Wikipedia:Wikipedia]
acre based unit
acre
"An area unit which is equivalent to 1 furlong x 1 chain. This is equal to an area of 4,046.856,4224 square meters, or 43,500 square feet." [Wikipedia:Wikipedia]