iodine
/ˈaɪəʊdiːn/noun
mass noun
1- the chemical element of atomic number 53, a non-metallic element forming black crystals and a violet vapour.(Symbol: I)（化学元素） 碘（符号： I ）。
1.1
- a solution of this in alcohol, used as a mild antiseptic碘酒。
A member of the halogen group, iodine occurs chiefly as salts in seawater and brines. As a constituent of thyroid hormones it is required in small amounts in the body, and deficiency can lead to goitre.
词源
early 19th cent.: from French iode （from Greek iōdēs 'violet-coloured'， from ion 'violet' + -eidēs 'like'） + -INE4.