English unit of area of land. It is equal to one chain (four rods) in width by one furlong in length, or 4840 square yards.

Unit of area in metric system (symbol a) used to express agrarian areas. It is equal to 100 square meter.

An area equal to that which can be ploughed by one eight-oxen team in a single year (also called a plough or carve). Approximately 120 roods.

Unit of area, also called cmil, which's equal to the area of a circle with a diameter of one mil (symbol cmil).
It is especially used to denote the cross-sectional size of a wire or cable. 1 mil = 0.001 inch.
Hence,

1 circular mil = π/4· 10^{-6} in² = 506.7075 μm².

Unit of area in metric system (symbol ha), mutiple of are used to express agrarian areas. It is equal to 100 are or 10000 square meter.

Imperial unit of area equal to one quarter of an acre or 40 square rod. It is equivalent to the area of one furlong in length and one rod in width.

Imperial unit of area equal to fathom by fathom.

Imperial unit of area (symbol ft²) derived from foot by foot or 0.09290304 m² exactly.

Imperial unit of land measurement equal to furlong by furlong.

Imperial unit of area (symbol in²) derived from inch by inch or 0.00064516 m² exactly.

Imperial unit of land equal to league by league.

Unit of area, which's equal to the area of a square with sides of length one mil. It is usually used in specifying
the area of the cross section of a wire or cable.
1 mil = 0.001 inch.Hence

1 square mil = (0.001 x 0.0254)² = 1.273 circular mil

Imperial unit of land equal to statute mile by statute mile.

SI unit for area (symbol m²) derived from SI base unit meter by meter.

Imperial unit of area (symbol yd²) derived from yard by yard or 0.83612736 m² exactly.