Army wiki:
y (from French armée) can, in some countries, refer to any armed force. More commonly, however, it is only used specifically to refer to a land force of the military.Within a national army, an army can also refer to a large formation, usually comprising one or more corps.Army is also often used in the description or title of military or paramilitary organisations which are not part of a country's official armed forces (and may well be illegal), such as the Irish Republican Army, and also in some non-military organisations organised on a quasi-military basis, such as the Salvation Army and the Church Army.
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