one of the administrative divisions of a large city
"New York City is divided into five distinct boroughs, each functioning as an important administrative unit within the metropolis."
an English town that forms the constituency of a member of parliament
"The new election results showed a victory for the Labour candidate in every borough across London."
A fortified town.
"The ancient borough still retains its massive stone walls and defensive moat from centuries past."
The area, properly called Southwark, just south of London Bridge, which is at the north end of Borough High Street (OS grid ref TQ3279).
"The historic market hall stands in the borough known as Southwark, situated just south of London Bridge and marking the northern terminus of Borough High Street."
From Middle English borwe, borgh, burgh, buruh, from Old English burh, burg, from Proto-West Germanic burg, from Proto-Germanic burgz ("stronghold, city"). Cognate with Dutch burcht, German Burg, Swedish borg, French bourg, Turkish burç. Doublet of Brough, burgh, and Bury.