Jump To:

• monkey wrench
  monkey wrench

  noun

  a wrench having an adjustable jaw permitting it to grasp nuts or the like of different sizes.
• monkey-wrench
  monkey-wrench

  verb (used with object)

  to ruin (plans, a schedule, etc.) unavoidably or, sometimes, deliberately.

monkey wrench

¹ American  

noun

1. especially British, adjustable spanner.  a wrench having an adjustable jaw permitting it to grasp nuts or the like of different sizes.

2. something that interferes with functioning; obstacle.

   He threw a monkey wrench into our plans.

---

monkey-wrench ² American  

[muhng-kee-rench] / ˈmʌŋ kiˌrɛntʃ /

verb (used with object)

1. to ruin (plans, a schedule, etc.) unavoidably or, sometimes, deliberately.

   The storm monkey-wrenched our plans for a picnic.

---

verb (used without object)

1. to prevent, delay, or sabotage industrialization or development of wilderness areas, especially through vandalism.

monkey wrench British  

noun

1. a wrench with adjustable jaws

---

Other Word Forms

• monkey-wrencher
  noun

Etymology

Origin of monkey wrench¹

First recorded in 1855–60

Origin of monkey-wrench²

First recorded in 1800–10

Example Sentences

See Examples For:

monkey wrench monkey-wrench

And part of their idea was you throw a monkey wrench into this process to stop it.

From Salon ● Aug. 5, 2023

“The last thing that a booming economy needs is to throw a monkey wrench into a system that we have that is working marvelously well.”

From Seattle Times ● Jul. 12, 2023

“You’ve thrown a monkey wrench into your campaign.”

From Washington Post ● Oct. 8, 2022

That has thrown a monkey wrench into the C919 programme, which has been in development for 13 years - one of the longest such periods in aviation.

From Reuters ● Sep. 27, 2021

Even worse, Vonetta had thrown a king-sized monkey wrench into my plans.

From "One Crazy Summer" by Rita Williams-Garcia

If Venezuela or any other country launched a surprise attack on the United States, I wouldn’t want the courts to monkey-wrench our prompt response.

From Los Angeles Times ● Mar. 25, 2025

But the court has yet to decide other pending cases that could monkey-wrench the regulatory system.

From Slate ● May 30, 2024

They’re a frisky if harmless sort of monkey-wrench gang, taking their last rolls with life’s fuzzy dice.

From New York Times ● Sep. 6, 2021

She delivers a satisfying, dramatic climax that represents the comeuppance of 19th-century colonialism, as Naila and the half brothers monkey-wrench the tools of the oppressor.

From Washington Post ● Mar. 25, 2019

I can’t decide whether it needs a monkey-wrench or a mustard-plaster.

From The Valiants of Virginia by Rives, Hallie Erminie