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monkey wrench

monkey wrench

1 7.0
An unexpected problem that causes trouble with a plan
  • noun
  • /ˈmʌŋki rɛntʃ/
  • Informal
translation icon : obstáculo inesperado
  • They faced a monkey wrench when their main supplier went out of business.
  • throw a monkey wrench

Then you throw the Cambridge Analytica monkey wrench.

Examples

  • OK, so that throws a bit of a monkey wrench into my plan.

  • Now that seems to throw a big monkey wrench into any notion of law.

  • Her sudden illness threw a big monkey wrench into our travel plans.

  • The unexpected rainstorm put a monkey wrench in our outdoor event.

Synonyms

pitfall
vsmonkey wrench
35 4.8

An unexpected problem that is not obvious at first

is more apparent and directly interferes with plans
snag
vsmonkey wrench
25 4.6

An unexpected problem that delays a plan

is broader, covering interference beyond just delays
rub
vsmonkey wrench
  • Informal
22 7.7

An unexpected problem that makes a plan or situation more difficult

focuses more on general interference than added complexity
spanner in the plan
vsmonkey wrench
  • UK
7.0

A sudden problem that stops plans from happening

is identical in meaning and use
unexpected roadblock
vsmonkey wrench
4.2

A sudden problem that stops progress and causes delay

is similar but covers obstacles in any plan or process

Antonyms

1.0

Getting what you want after working hard

smooth sailing
  • Informal
16 2.7

An easy time with no problems

How Disruptive

catastrophe
176 7.0
crisis
3.1
monkey wrench
  • Informal
1 7.0
problem
1.2
setback
148 3.6

Surface Forms

monkey wrench singular

Morphology

monkey + wrench

The idiomatic meaning 'an unexpected problem' is metaphorically derived from the idea of a wrench (a tool) being thrown into machinery to disrupt it; this gives some clue to disruption but requires inferencing beyond the literal constituents. Because the role of 'monkey' is not transparently related to the obstacle meaning and the phrase relies on a cultural metaphor (compare British 'throw a spanner in the works'), a B1 learner who only knows the individual words may not reliably predict the idiomatic sense.

Etymology

Monkey wrench as an idiom comes from the image of throwing a monkey wrench into the gears of a machine to stop them. So it means 'an unexpected problem' that gets in the way of a plan.