by the book

Cultural  

1. According to established rules: “The inspector will be visiting the factory today, so let's make sure we do everything by the book.”

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by the book Idioms  

1. Strictly according to the rules, as in Our trip leader is going by the book, allowing us to wander off only for short periods. Shakespeare already used the term figuratively in Romeo and Juliet (1:5): “You kiss by the book.” Also see by the numbers.

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Example Sentences

You’re doing pretty much everything by the book.

From MarketWatch • May 14, 2026

There is a second, diffuse—seemingly unintentional—sadness revealed by the book that is something closer to cultural or civilizational loss.

From The Wall Street Journal • Feb. 23, 2026

The company, which underwent several acquisitions, including by the book retailer Barnes & Noble, was later renamed GameStop.

From Los Angeles Times • Jan. 16, 2026

Tonga coach Kristian Woolf defended the team doctors, saying everything was "done by the book".

From Barron's • Nov. 3, 2025

Even his paintbrush was by the book, made from the tip of a squirrel’s tail.

From "Middlesex: A Novel" by Jeffrey Eugenides

Related Words

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