monkey business

American  

noun

1. frivolous or mischievous behavior.

2. improper or underhanded conduct; trickery.

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monkey business British  

noun

1. informal mischievous, suspect, dishonest, or meddlesome behaviour or acts

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monkey business Idioms  

1. Silly, mischievous, or deceitful conduct, as in The teacher told the children to cut out the monkey business and get to work, or I don't trust that lawyer—there's some monkey business going on. This expression transfers the tricks of monkeys to human behavior. [Late 1800s]

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Etymology

Origin of monkey business

An Americanism dating back to 1880–85

Example Sentences

“That was more than enough monkey business for us,” the department said in a post on X, formerly known as Twitter, to announce Momo’s capture.

From Seattle Times • Oct. 5, 2023

The days of monkey business may be over.

From Slate • Oct. 12, 2022

Giuliani was hoodwinked not by a monkey but old-fashioned monkey business.

From Salon • Oct. 23, 2020

Suffice it to report, that’s a whole bunch of monkey business.

From Washington Times • Nov. 29, 2018

“And I think we’d better keep this monkey business to ourselves. If word gets out, every farmer in these hills will quit farming and start hunting monkeys. We can’t have that at all.”

From "Summer of the Monkeys" by Wilson Rawls