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

Daily says he's particularly proud to be helping small, family-owned businesses like his mother's and grandfather's.

From BBC • Mar. 25, 2026

Large firms such as JPMorgan aren’t the only ones that compete for government advisory business—smaller banks, investment partnerships and family-owned businesses are also covered.

From The Wall Street Journal • Oct. 24, 2025

Newsom said the crackdown was also harming family-owned businesses as immigrants who work and shop at stores stay home out of fear.

From Los Angeles Times • Jul. 16, 2025

Find less-crowded restaurants in the evenings and easy shopping and tastings from family-owned businesses during the day.

From Seattle Times • Dec. 19, 2022

By the late fifteenth century, Italian city-states were supporting a variety of small family-owned businesses and large companies.

From Textbooks • Dec. 14, 2022