A hectad is an area 10 km x 10 km square.
The term has a particular use in connection with the British
Ordnance Survey
The Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see Artillery, ordnance and surveying), which was to map Scotland in the wake of the Jacobite rising of ...
national grid, and then refers to any of the 100 such squares which make up a standard 100 km x 100 km
myriad; these are denoted using the letter code of the 100 km square, and then a two-digit number consisting of the one-digit
easting of the western bound of the hectad and the one-digit
northing
A projected coordinate systemalso called a projected coordinate reference system, planar coordinate system, or grid reference systemis a type of spatial reference system that represents locations on Earth using Cartesian coordinates (''x'', '' ...
of its southern bound.
See also
*
Tetrad (unit of area)
References
Units of area
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