French Expressions and Idioms
Have you heard of “idiomatic expressions”? These are figurative expressions specific to French, that are usually not translatable directly, as each language uses its own references! Therefore, you need to learn them directly in the language, as well as learning French equivalents to the ones you use in English! Knowing idiomatic expressions is key when learning a new language and it will definitely help you sound like a true Français 😊
✍️ Today’s French expression is:

“Être un rat de bibliothèque”
🎧 Here’s a podcast about it!
Want to learn more about this fun expression, what it means, and hear some in-context examples? Then listen to Aurélie and Céline‘s related podcast below:
🐀📚 Some context
The French expression être un rat de bibliothèque (literally “to be a library rat”) dates back to the 18th century. It was inspired by the actual rodents that crept into dark archive rooms to gnaw on old paper and book bindings. It also follows a classic French pattern of using “rat of [a place]” to describe someone who spends a lot of time in a specific spot, much like a church rat or an opera dancer (petit rat de l’Opéra). While the phrase originally carried a slightly negative connotation, describing a reclusive person with purely bookish knowledge, today – much like its English equivalent, “bookworm” – it is used neutrally or affectionately to describe avid readers and dedicated researchers who love spending their time immersed in books.
👀 How about some examples?
To help you commit this expression to memory, here are some useful examples of how to use it in context:
- Mon frère passe tous ses samedis après-midi à la médiathèque ; c’est un vrai rat de bibliothèque.
- Pendant la rédaction de sa thèse de doctorat, Léa est devenue un véritable rat de bibliothèque.
- Ma fille Leila a toujours été un vrai petit rat de bibliothèque : elle dévorait tous les livres qui lui passaient sous la main.
- Ce n’est qu’après avoir découvert l’univers du” Seigneur des Anneaux” que je suis devenu un authentique rat de bibliothèque.
🤩 Enjoy a special Fill-in-the-Blanks exercise!
With this great Fill-in-the-Blanks exercise featuring our new expression, you get to practise your French grammar while getting another in-context use of the expression “être un rat de bibliothèque” to help you remember it 🤗 Que demander de plus ?
- Souvenirs d’un rat de bibliothèque (L’Imparfait) – A2
🙌 Now is your time to shine!
Challenge yourself to use these expressions in a French conversation or piece of writing, and let us know what you thought of this expression, share your idiomatic sentences, and tell us how your French friends reacted to it – en français bien sûr – in the comments below ☺️
À toi de jouer !