A farl (reduced form of the Scots fardel) is any of various quadrant-shaped flatbreads and cakes, traditionally made by cutting a round into four pieces.
In Northern Ireland, the term generally refers to soda bread and to potato bread or cakes (potato farls). While soda bread can also be baked as a normal loaf, that used in an Ulster fry breakfast is made as farls (that is to say, flat rounds about 3/4 inch thick which are then cut into quarters). Modern commercially mass-produced potato farls, however, are often rectangular in form.
In Scotland today, the word is used less than in Northern Ireland, but a farl can be a quarter piece of a large flat scone, bannock, or oatcake. It may also be used for shortbread when baked in this particular shape