The British Isles is the collective name for the islands of Britain, Ireland, the Isle of Man, the Channel Islands and all of the surrounding islets. The term is used mainly referring to weather and nature stuff, and also has some cultural use. Some Irish people have hard reservations about the term being applied to the island of Ireland, and so the British and Irish governments no longer use it. But Irish people who are not insecure about Ireland's future have no problem with the term, recognising that its just the name of a place, not a secret government.

Origin: Britain and Ireland were called "Britain" and "Britanis" in Roman times, which translates as Great Britain and Little Britain.
"This species of owl can be found throughout the British Isles.."

"Ireland was separated from the British Isles in 1922, we went out and cut it loose, so fuck off with your owls"
by Robert_HS March 11, 2006
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The British Isles are an archipelago of islands off North-Western Europe. The two largest islands are Great Britain and Ireland. Great Britain consists of three countries: England, Wales and Scotland. Ireland consists of two countries: Northern ireland and the Republic of Ireland. Great Britain together with Northern Ireland make up the United Kingdom of Great Britain and Northern Ireland (UK).
Many people mistake England for an island, which is because of the extensive use of English as a vernacular across the island of Great Britain (although Welsh and Gaelic are also used a lot). England is just one of the countries of Great Britain, if one is to call it a country, as it does not have its own government (unlike Scotland and Wales). Britain and England are not interchangeable, despite England having the UK capital.
The British Isles has five different countries.
England is not one of the islands of the British Isles!
by jthom9 January 22, 2009
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All the islands which make up Great Britain (England, Scotland and Wales) *plus* the Republic of Ireland and Northern Ireland. That's right - the 'British Isles' include Ireland, much to the chagrin of the Irish!
"I'm from Dublin, you know, in the *British Isles*" !!!
by Al Dente November 21, 2007
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