throw a monkey wrench in the works

Proposed by a contributor, not yet supported by evidence.

Meaning · English

To cause problems or disrupt plans

Literally: throw a monkey wrench into machinery
Where it’s used: Used Widespread English

Examples

The unexpected rain threw a monkey wrench in the works of our outdoor wedding

AI-drafted example auto-approved by rule (illustrative, not a corpus attestation)

Sources & notes

Listed in Wiktionary’s “English idioms” category (retrieved 2026-07-29); definition pending editorial review. Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-31; pending editor spot-check.

Common questions

What does “throw a monkey wrench in the works” mean?

To cause problems or disrupt plans Literally: throw a monkey wrench into machinery

Is “throw a monkey wrench in the works” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.