"The controlling financial interests of the United States."

Wall Street (w?l)
n.
The controlling financial interests of the United States.
[After Wall Street in New York City.]
Wall-Streeter (w?lstrtr) n.

The American Heritage? Dictionary of the English Language, Fourth Edition copyright ?2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
Wall Street
n
1. (Placename) a street in lower Manhattan, New York, where the Stock Exchange and major banks are situated, regarded as the embodiment of American finance

Collins English Dictionary – Complete and Unabridged ? HarperCollins Publishers 1991, 1994, 1998, 2000, 2003