How did the monkey wrench get its name?

The term "monkey wrench" dates back to 1807 in Great Britain. Referring to the tool, the phrase appears in E.S. Dane’s "Peter Stubs & Lancashire Hand Tool Industry" catalog, which reads "Fleetwood, Richard...Parr, Rainford. Screw plates, lathes, clock engines...monkey wrenches, taps."

In 1858, Charles Moncky of Baltimore, Maryland, applied for a patent for the monkey wrench. Some believe the term monkey wrench is a derivation of Mr. Moncky's name, but its use in Great Britain in 1807 negates this assumption.

The phrase "throwing a monkey wrench," meaning the creation of an obstacle, dates to a 1907 article in the Chicago Tribune, which reads: "It should look to them as if he were throwing a monkeywrench..."