English Reference

Word

iodine

Phoneticsio·dine

US/ˈaɪəˌdaɪn/

UK/ˈaɪədˌiːn/

Definition

n. a chemical element that is important for your health. It is often used to clean cuts or added to salt to help your body work correctly.

n. a nonmetallic chemical element of the halogen group, appearing as a dark-violet solid that sublimes into a purple gas. Essential for thyroid function and widely used as an antiseptic or in medical imaging.

Examples

“The doctor used iodine to clean the wound before the surgery.”

“Many countries add iodine to table salt to prevent health problems caused by a lack of this nutrient.”

“In the event of a nuclear emergency, potassium iodine tablets are distributed to prevent the thyroid gland from absorbing radioactive isotopes released into the atmosphere.”

Examples

simple

“The doctor used iodine to clean the wound before the surgery.”

contextual

“Many countries add iodine to table salt to prevent health problems caused by a lack of this nutrient.”

complex

“In the event of a nuclear emergency, potassium iodine tablets are distributed to prevent the thyroid gland from absorbing radioactive isotopes released into the atmosphere.”

Usage

Uncountable when referring to the chemical element or the liquid antiseptic solution.

Real-World Examples

“The process involves naturally occurring iodine, sulfur, and organic compounds that are released into the air and contribute to the formation of new atmospheric particles.”
ScienceDaily · 18 Aug 2026
“The stench of acrid smoke was vile, but the valuable iodine-rich ash could be sold to iodine factories on the northern coast for glass making.”
BBC · 25 Feb 2022

Etymology

From French iode + -ine, from Ancient Greek ἰοειδής (ioeidḗs, “violet”). Coined by British chemist Humphry Davy in 1814.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

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English Reference