A word used by many British and common wealth Military personel in the 19th and 20th Centuarys.
It basically means charge.
Unfortunatly from the 1950's to the present day, this has become a common steriotype in america for what British people say when in fact that has been said more often in america than it ever has in Britain.
Mr. JohnEveryAmerican : Hay look a british person, Tally ho pip pip
Mr. Englishman : Fuck off you Bell End