# iodine

/ˈaɪəˌdaɪn/ (US) · /ˈaɪədˌiːn/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/iodine
Updated: 2026-05-07

## Definition

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.

For teachers: 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.

## Usage notes

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

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