Originally refered to English cricket supporters traveling to Australia to watch the ashes series in 1994/95. Barmy because of all the money they spent to get there to warch a team who had no hope of winning (they didn't). Army because of the 100's of them who would all sit together, cheering on and supporting the team.

It is now generally used for any large group of English cricket supporters on tour anywhere in the world. It can occasionally be used to include other English teams - It's use for rugby is just about acceptable but certainly not for football.
'Atherton's Barmy Army'
by Revrat October 23, 2007
A group of excelled individuals who have formed a young gentleman's club in order to promote unity and organised drinking within a group dynamic. Each member brings their own unique and special attributes to the club, be it their individual take on barmyness or extremely strong banter. Entrance to this elitist and profound club is on an invite only basis and a series of tasks and initiations must be passed before granted membership.

The Barmy Army frowns upon anti-banter and 'banter sappers' and also doesn't permit disloyalty such as, 'I'm not hammered, I'm Birmingham hammered!' Such comments result in members being re-initiated and discriminated against.

Members of The Barmy Army take this gentleman's club extremely seriously and intend to rival The Masons.
i strive to one day meet a member of the barmy army.
by Sir D.M.Broadfield January 10, 2009
Enthusiastic club (circa Euro '96 onwards) of supporters of the England football team who travel the world to see their team play.

They sell branded shirts which are bought by adolescent thugs who don't understand the irony.
barmy army...barmy army...barmy army...
(through the whole 90 minute game).
by English Boy December 8, 2004
Pathetic, Overated Hype invented by New Zealand's Imperialist-Scum Media used to create public hype and exploit the game of rugby when no such other hype exists for Wallaby or Springbok games of which are held more than once a year.
just cos the those barmy army lions play in NZ only once every 12 years, it doesnt make it any different from the Australians or South Africans who play here for 3 weeks per team at a time every year, this Barmy Army shit is majorly over-rated.
by Brother Number One June 29, 2005
A group of middle-class yobs, usually aged between 10-18 who feed off threatening Asian shopkeepers and mistreating their homework. Smoking mediocre rollies and keeping their collars 'fashionably upright', the Bingham Barmy Army (BBA) will stop at nothing until the small, isolated town is there's for the taking!
My name is James Oliver John Clark and i'm in the "Bingham Barmy Army (BBA)", got a problem with that!?
by BigManNatty January 8, 2014
Army-barmy is when a squaddie is so obsessed and in love with the army and military things in general that his entire life revolves around being cammed up,ops,and generally ready to mangle,strangle,stab,shoot or shag anything or anyone, with, and possibly without, a pulse.Not just being content to keep these awe-inspiring facts to himself he will persist in droning on for hours and hours about his impressive knowledge of the martial art thus boring shitless his family,friends and neighbours.The ROYAL MARINES and the PARA-REG are famous for this affliction.
My brother became army-barmy after joining the guards,his wife once told me (after we'd being shagging one day)that even on their honey-moon he'd insist on inspecting her feet for blisters before bed and in the morning he'd wake her up with bucket of cold water and an enthousiastic "Hands off cocks, on socks!"
by Steve CHUTER November 27, 2006