noun

fluorine

FLOOR-in

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Fluorine (noun) means Fluorine is a pale yellow-green gas and the lightest of the halogen elements, with the symbol F and atomic number 9. Example: “Fluorine is so reactive that it attacks almost every metal it touches.”

noun

Fluorine is a pale yellow-green gas and the lightest of the halogen elements, with the symbol F and atomic number 9.

"Fluorine is so reactive that it attacks almost every metal it touches."

"The gas has a pale yellow-green colour that helps chemists identify it in the lab."

"As the lightest halogen, fluorine sits at the top of its group on the periodic table."

How to use fluorine

Learner’s notes

In plain EnglishFluorine is a very reactive, pale yellow-green gas and the lightest of the halogen elements.

When to use it

Fluorine is a technical, scientific term used mainly in chemistry contexts.

Memory tip

Remember fluorine is the element itself, a gas, while fluoride is a compound that contains it.

Trace the full origin ↓

Easily confused with

fluoride → fluorene

Common pairings

fluorine gas fluorine atom fluorine compound highly reactive fluorine

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C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

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Fill the gap

Can you complete this real example?

_____ is so reactive that it attacks almost every metal it touches.

Etymology

Fluorine comes from the Latin word fluor, meaning flow, combined with the English suffix -ine. The British chemist Humphry Davy coined the name in 1813.

Origin: Latin

Rhymes for fluorine

nine mine wine line sine ovine amine thine shine Rhine Maine seine

See all rhymes for fluorine →

Frequently asked questions

What is fluorine used for?

Fluorine itself is too reactive to use directly, so its compounds are used instead, such as fluoride added to drinking water and toothpaste, and other fluorine compounds used in refrigerants and non-stick coatings like Teflon.

Is fluorine dangerous?

Yes, fluorine is a highly reactive, corrosive gas that attacks almost all metals, so it has to be handled with great care.

Who named fluorine?

The British chemist Humphry Davy coined the name in 1813, drawing on the Latin word fluor, meaning flow.

What is the meaning of fluorine?

"fluorine" (noun) means fluorine is a pale yellow-green gas and the lightest of the halogen elements, with the symbol F and atomic number 9.