Beltway bandit is a term for private companies located in or near Washington, D.C., whose major business is to provide consulting services to the federal government of the United States.
The phrase was originally a mild insult, implying that the companies preyed like bandits on the generosity of the federal government, but it has lost much of its pejorative nature and is now often used as a neutral, descriptive term.
[1][2] The term refers to the Capital Beltway, which is a ring road that surrounds Washington.
[2] An early use of the term may have been from a description of thieves who took advantage of the newly constructed Beltway to rob houses from their back yards, which were now exposed to the highway.
[3] "The Beltway Bandits" is an instrumental piece of music by Frank Zappa on his 1986 Jazz from Hell album.