What do they call Canadian bacon in England?
Even though Americans call this bacon Canadian bacon, most other countries, including Canada, will refer to it as back bacon, since the meat comes from the back of the pig.
Canadian bacon, also called back bacon or rashers, comes from the pork loin of a pig. The dish originated in Canada and is different from American-style bacon (also called streaky bacon), which comes from pork belly and has much more fat.
American-style bacon is readily available in the UK, but it is known as "streaky bacon" due to the streaks of fat running along it.
In the United Kingdom, a pork leg cut, either whole or sliced, that has been cured but requires additional cooking is known as gammon. Gammons were traditionally cured before being cut from a side of pork along with bacon. When cooked, gammon is ham.
In America 'bacon' comes from the belly of the pig. Whereas, according to Wikipedia bacon in the UK typically comes from the back of the pig (we call this canadian bacon). Either way these are usually dry-cured. Gammon cuts come from the hind legs of the pig.
The main thing that separates these breakfast staples is where they come from on a pig: Ham comes from the back legs, specifically the thighs and rear end, while Canadian bacon comes from the back. There are many different types of ham, while there is only one type of Canadian bacon.
Canadian bacon is cut from the loin of the pig, so this is thicker, meatier and very lean. British bacon is cut from the loin with a little part of the belly attached. This makes it much meatier than American bacon, but with the addition of the belly it is less dry than the Canadian bacon.
Pancetta is the same cut as American bacon, so that's the first substitute that comes to mind. Canadian bacon, salt pork, prosciutto, smoked ham, and smoked sausage are all good choices as well.
To make up for the shortfall, pork was imported from Canada. The British used this lean loin of the pig's back to make what was called peameal bacon since it would be rolled in ground split yellow peas after it was cured in a special brine. It then became known as Canadian bacon.
Here in the UK, for instance, sausages are affectionately known as 'bangers', as in 'bangers and mash'. This dates back to before the Second World War, when meat was scarce.
What is American bacon called in Ireland?
Bacon in England and Ireland is also usually back bacon, although it often is cut in a way that leaves more fat around the meat.
The Full English Breakfast (AKA The Fry Up)
The 'common' full English breakfast is a substantial meal consisting of back bacon, eggs, British sausage, baked beans, bubble and squeak, fried tomato, fried mushrooms, black pudding, with fried and toasted bread on the side.

Courgette (UK) / Zucchini (US)
A biscuit is a cookie. A British person would only call chocolate-chip biscuits a cookie. Scones are a baked item made of firm dough. They are neither soft like bread or crisp like a cookie or a biscuit but are somewhere in between, a bit like the shortcake in strawberry shortcake, or American biscuits, except sweet.
In England, biscuits are cookies--usually hard and crisp. What Americans call biscuits are known as rolls or quickbreads.
Canadian bacon is cut from the loin of the pig, so this is thicker, meatier and very lean. British bacon is cut from the loin with a little part of the belly attached. This makes it much meatier than American bacon, but with the addition of the belly it is less dry than the Canadian bacon.
Some Americans refer to peameal bacon as 'Canadian bacon'. However, 'Canadian-style bacon' or 'Canadian back bacon' are terms used by the U.S.-based North American Meat Institute for an American style of smoked back bacon. This may be sold in U.S. supermarkets as 'Canadian bacon', but is not Canadian.
Irish bacon is traditionally made from the back of the pig as opposed to the pork belly commonly used in American bacon. In this sense it is more similar to Canadian bacon; both Canadian and Irish bacon are referred to as back bacon but the Irish variety has more fat and often cut into a round shape.
Canadian bacon comes from the loin cut of the pig, which is located on the back of the pig. This cut is what gives Canadian bacon its nickname of "back bacon." Alternatively, ham comes from the leg or butt of the pig. While the type of animal (pig) may be the same, the location, or cut, of the meat is different.