Troop

A troop is a military sub-subunit, originally a small formation of cavalry, subordinate to a squadron. In many armies a troop is the equivalent element to the infantry section or platoon. Exceptions are the Royal Horse Artillery and the US Cavalry, where troops are subunits that compare to an infantry company or artillery battery.

A cavalry soldier of private rank is called a trooper in many Commonwealth armies (abbreviated "Tpr", not to be confused with "trouper").

A related sense of the term "troops" refers to members of the military collectively, as in "the troops"; see .

In some countries, like Italy, the company-level cavalry unit is called "Squadron".

Today, a troop is defined differently in different armed forces.

In the Australian Army a troop is the equivalent of a platoon sized element in units of certain corps, those being:

The SASR is the only unit in the Royal Australian Infantry Corps to use the term troop to refer to its platoon size elements. SASR troops are also unusual as they are commanded by a captain—most troop/platoon sized elements are commanded by a lieutenant. In all cases, units which refer to platoon sized elements as troops refer to company-sized elements as squadrons and battalion-sized elements as regiments. Privates in the RAAC and SASR hold the rank "trooper", however this is not the case for any other Corps/units which use the term troops.

In the British Army the definition of a troop varies by corps.

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