monkey wrench

[butter007]

Hello my dear teachers,

I came across this phrase and although my intuition told me what it might mean, the dictionary made me feel confused with its technical explanation. Thank you! God bless you.

The whole phrase: to put a monkey wrench into o.s. business machinery...

butter007

[Searching for language]

It means that something has occurred so that you cannot do as you had planned.

for example: We had planned to go on a bicycle ride in the country, but my bicycle had a flat tire.

The flat tire became "the monkey wrench" in our plans.

[Ouisch]

In BrE, they call this particular tool an "adjustable spanner." So you'll find a similar expression "a spanner in the works" in British publications. As Searching said, it is an idiom for some obstacle that derails a plan or event or process.

(By the way, the monkey wrench got its name from its inventor, Charles Moncky.)