Private
A private, short for "private soldier", is a soldier of the lowest military rank.
Private insignia
(U.S. Army)
In the U.S. Army, Private refers to the two lowest enlisted ranks, just below Private First Class. The lowest rank wears no uniform insignia, while the second wears the insignia shown here. Advancement to the higher version of private (with insignia) is currently automatic after 6 months time in service, but may get shortened to 4 months if given a waiver.
In the U.S. Marine Corps, Private refers to the lowest enlisted rank, just below Private First Class. A marine corps private wears no uniform insignia.
In the British Army, many regiments and corps have distinctive (and descriptive) names for this rank, such as Trooper (Tpr), Sapper (Spr), and Craftsman (Cfn).
In the Royal Marines the equivalent rank is Marine.
Private is also the title of a European porn magazine.