The name of a
city in
England in the
United Kingdom. There's also a
New Wilmington.
It's also an American city name, as in Wilmington, NC, Wilmington, DE, Wilmington, OH, or Wilmington, VT. No doubt these are all named after the British city in one way or another. Several of them apparently changed their names to Wilmington in 1739 because of Spencer Compton, who was the Earl of Wilmington, a member of Parliament, and a favorite of King George II.
Sources:
http://www.ego.net/us/nc/ilm/history/col.htm
http://www.ci.wilmington.nc.us/cityfacts.html
http://www.ci.wilmington.de.us/demographics.htm
http://www.ci.wilmington.oh.us/
http://www.britannia.com/gov/primes/prime2.html