A borough is an administrative division in various countries. In principle, the term borough designates a self-governing township although, in practice, official use of the term varies widely.

The word borough derives from common Germanic *burg, meaning fort: compare with bury (England), burgh (Scotland), Burg (Germany), borg (Scandinavia), burcht (Dutch) and the Germanic borrowing present in neighbouring Indo-european languages such as borgo (Italian), bourg (French) and burgo (Spanish and Portuguese). The incidence of these words as suffixes to place names (for example, Canterbury, Strasbourg, Luxembourg, Edinburgh, Hamburg, Gothenburg) usually indicates that they were once fortified settlements.

In the Middle Ages, boroughs were settlements in England that were granted some self-government; burghs were the Scottish equivalent. In medieval England, boroughs were also entitled to elect members of parliament. The use of the word borough probably derives from the burghal system of Alfred the Great. Alfred set up a system of defensive strong points (Burhs); in order to maintain these settlements, he granted them a degree of autonomy. After the Norman Conquest, when certain towns were granted self-governance, the concept of the burh/borough seems to have been reused to mean a self-governing settlement.