yard, abbr. yd, basic unit of length in the customary system of English units of measurement; all other units in the English system, such as the inch, foot, rod, and mile, are derived from it. Since 1893 the yard has been defined in terms of the meter, the basic unit of length in the metric system. For a long time the yard was held to equal 3600/3937 of a meter; it has since been recalculated so that 1 yd equals 0.9144 m. In the United States results of geodetic surveys are still expressed in feet based on the former definition of the yard; this is known as the U.S. Survey Foot, defined as 1200/3937 of a meter.

Scotland Yard, headquarters of the London Metropolitan Police. The term is often used, popularly, to refer to one branch, the Criminal Investigation Department (CID). Named after a short street in London, the site of a palace used in the 12th cent. as a residence of visiting Scottish kings, it became London's police center in 1829. New and separate headquarters for the Metropolitan Police were built in 1890 along the Thames embankment and were referred to as New Scotland Yard. In 1967, New Scotland Yard moved to new headquarters, also in the Westminster area.

officially New Scotland Yard

Headquarters of the London Metropolitan Police, and, by extension, the force itself. The London police force was created in 1829 by Sir Robert Peel and housed at 4 Whitehall Place, which had an entrance in Great Scotland Yard. In 1890 it moved to a new building; that location became New Scotland Yard, a name that was kept when it moved again in 1967. In addition to duties common to all metropolitan police forces (including crime detection and prevention and traffic management), it is entrusted with civil defense in times of emergency, and it maintains a special branch for guarding visiting dignitaries, royalty, and political dignitaries. It keeps records on all known criminals in Britain, and other British police forces often seek its assistance. It also helps train the police of Commonwealth nations.

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