fluorine

noun

fluo·​rine ˈflu̇r-ˌēn 

ˈflȯr-

: a nonmetallic gaseous chemical element of the halogen group with atomic number 9 that readily forms compounds with almost all other elements including some noble gases see Chemical Elements Table

Examples of fluorine in a Sentence

Recent Examples on the Web

Rather than radiation, the greater risk might be from fluorine, which is used to enrich uranium and could have been deadly to those nearby if released during an attack. —Emma Burrows, Chicago Tribune, 14 June 2025

One problem is that many lithium-ion batteries today contain fluorine, which readily combines with hydrogen to make hydrofluoric acid (HF). —IEEE Spectrum, 1 Mar. 2013

Rather than radiation, experts said a bigger risk from any attack on nuclear enrichment sites might be from fluorine gas. —Shane Croucher, MSNBC Newsweek, 20 June 2025

As expected, all 13 of those bands were found to contain fluorine, a hallmark of PFAS usage. —Michael Franco, New Atlas, 18 Dec. 2024

Word History

Etymology

French, from New Latin fluor

First Known Use

1813, in the meaning defined above

Rhymes for fluorine

• agin
• alkene
• allene
• ameen
• amin
• amine
• arene
• athene
• baleen
• beeline
• benzene
• between

Kids Definition

fluorine

noun

flu·​o·​rine

ˈflu̇(-ə)r-ˌēn,

-ən

: a nonmetallic element that is normally found alone as a pale yellowish flammable irritating poisonous gas having two atoms per molecule see element

Medical Definition

fluorine

noun

fluo·​rine ˈflu̇(-ə)r-ˌēn  -ən 

: a nonmetallic monovalent halogen element that is normally a pale yellowish flammable irritating toxic gas

—symbol F see Chemical Elements Table