ENGLISH
REFERENCE

iodine

n. uncountable
C1 Advanced US //ˈaɪəˌdaɪn// UK //ˈaɪədˌiːn// io·dine Archaic

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.


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.

Synonyms
Origin

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

Usage

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

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