Borough

(in certain states of the U.S.) an incorporated municipality smaller than a city.
one of the five administrative divisions of New York City.
British.

an urban community incorporated by royal charter, similar to an incorporated city or municipality in the U.S.
a town, area, or constituency represented by a Member of Parliament.
(formerly) a fortified town organized as and having some of the powers of an independent country.

(in Alaska) an administrative division similar to a county in other states.
Contemporary Examples

Stop Moping! The Marathon Is Exactly What New York Needs Right Now Jay Michaelson November 2, 2012
DINO Hunters Are Dreaming Hipster Dreams of the DNC in Brooklyn David Freedlander August 11, 2014
‘Girls’: Inside the Eccentric Fashion of Lena Dunham’s HBO Comedy Alyssa Rosenberg January 9, 2013
The Daily Beast Recommends The Daily Beast May 4, 2009
Michael Showalter on Making the Publishing World More Comical, One Chapter at a Time Daily Beast Promotions February 24, 2011

Historical Examples

Quodlibet John P. Kennedy
The Uncommercial Traveller Charles Dickens
The Johnstown Horror James Herbert Walker
A Writer’s Recollections (In Two Volumes), Volume II Mrs. Humphry Ward
Encyclopaedia Britannica, 11th Edition, Volume 17, Slice 2 Various

noun
a town, esp (in Britain) one that forms the constituency of an MP or that was originally incorporated by royal charter See also burgh
any of the 32 constituent divisions that together with the City of London make up Greater London
any of the five constituent divisions of New York City
(in the US) a self-governing incorporated municipality
(in medieval England) a fortified town or village or a fort
(in New Zealand) a small municipality with a governing body
n.