Rood (unit)
Rood has several distinct meanings, all derived from the same basic etymology.
This article refers to the historic English and international inch-pound measure of area, as well as the archaic English measure of length.
Rood is an archaic word for "pole", from Old English rōd "pole", specifically "cross", from Proto-Germanic *rodo, cognate to Old Saxon rōda, Old High German ruoda "rod"; the relation of rood to rod, from Old English rodd "pole", is unclear; the latter was perhaps influenced by Old Norse rudda "club".
Rood is an English unit of area, equal to one quarter of an acre or 10,890 square feet (1,012 m2) or 0.10 hectares). A rectangle that is one furlong (i.e. 10 chains, or 40 rods) in length and one rod in width is one rood in area, as is any space comprising 40 perches (a perch being one square rod). The rood was an important measure in surveying on account of its easy conversion to acres. When referring to areas, rod is often found in old documents and has exactly the same meaning as rood.
A rood is also an obsolete British unit of linear measure between 16 1⁄2 and 24 feet (5.0–7.3 m). It is related to the German and the Danish . The original OED of 1914 said this sense was "now only in local use, and varying from 6 to 8 yards" (or 18 to 24 ft, "Rood", II.7).
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