iodine

[ahy-uh-dahyn, -din; in Chemistry also ahy-uh-deen]

noun Chemistry.

a nonmetallic halogen element occurring at ordinary temperatures as a grayish-black crystalline solid that sublimes to a dense violet vapor when heated: used in medicine as an antiseptic. Symbol: I; atomic weight: 126.904; atomic number: 53; specific gravity: (solid) 4.93 at 20°C.

Also i·o·din

[ahy-uh-din] /ˈaɪ ə dɪn/.

Origin of iodine

1814; < French iode (< Greek īṓdēs, orig. rust-colored, but by folk etymology taken as í(on) violet + -ōdēs -ode¹) + -ine²; introduced by H. Davy

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for iodine

Contemporary Examples of iodine

They said this phenomenon might have caused the level of iodine to rise before the tap water could reach the purifying plant.
Radiation in Tokyo's Tap Water
Lennox Samuels
March 23, 2011
At Chernobyl, iodine fell on the grass, cows ate the grass, and people drank the milk.
California's Nuclear Freakout
Josh Dzieza, Tricia Romano
March 18, 2011
The iodine plume itself is not the issue, agreed Brenner, but that it falls on the grass and cows eat it.
California's Nuclear Freakout
Josh Dzieza, Tricia Romano
March 18, 2011
Even at the Chernobyl meltdown in 1986, he pointed out, cesium and iodine were the problem.
The Toxic Fuel Inside Japan's Nuclear Plant
Eve Conant
March 15, 2011
One of the isotopes of fission products, when fuel melts, is an iodine isotope, and it goes in your body through your thyroid.
Japan Nuclear Fallout: How Bad Could It Get?
Josh Dzieza
March 12, 2011

Historical Examples of iodine

Crystals of iodine as opposed to permanganate of potash for antiseptic he discussed.
The Leopard Woman
Stewart Edward White
The doctors had vainly tried every remedy, iodine, blistering, and cauterising.
The Three Cities Trilogy, Complete
Emile Zola
The iodine will color the leaf dark where the cells contain starch.
Common Science
Carleton W. Washburne
You can tell what foods have starch in them by testing them with iodine.
Common Science
Carleton W. Washburne
The preparations of iodine have also been recommended, and they are very serviceable.
Cattle and Their Diseases
Robert Jennings

British Dictionary definitions for iodine

iodine

noun

a bluish-black element of the halogen group that sublimates into a violet irritating gas. Its compounds are used in medicine and photography and in dyes. The radioisotope iodine-131 (radioiodine), with a half-life of 8 days, is used in the diagnosis and treatment of thyroid disease. Symbol: I; atomic no: 53; atomic wt: 126.90447; valency: 1, 3, 5, or 7; relative density: 4.93; melting pt: 113.5°C; boiling pt: 184.35°C

Word Origin for iodine

C19: from French iode, from Greek iōdēs rust-coloured, but taken to mean violet-coloured, through a mistaken derivation from ion violet

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for iodine

1814, formed by English chemist Sir Humphrey Davy (1778-1829) from French iode "iodine," coined 1812 by French chemist Joseph Louis Gay-Lussac from Greek ioeides "violet-colored," from ion "the violet; dark blue flower," + eidos "appearance" (see -oid). Davy added the chemical suffix -ine (2) to make it analogous with chlorine and fluorine. So called from the color of the vapor given off when the crystals are heated.

Medicine definitions for iodine

iodine

[ī′ə-dīn′, -dĭn, -dēn′]

n.

A poisonous halogen element having compounds used as germicides, antiseptics, and food supplements, with numerous radioactive isotopes, which are used in diagnosis and treatment of thyroid diseases and neuroendocrine tumors. Atomic number 53.

A liquid containing iodine dissolved in ethyl alcohol, used as an antiseptic for wounds.

Science definitions for iodine

iodine

[ī′ə-dīn′]

I

A shiny, grayish-black element of the halogen group. It is corrosive and poisonous and occurs in very small amounts in nature except for seaweed, in which it is abundant. Iodine compounds are used in medicine, antiseptics, and dyes. Atomic number 53; atomic weight 126.9045; melting point 113.5°C; boiling point 184.35°C; specific gravity (solid, at 20°C) 4.93; valence 1, 3, 5, 7. See Periodic Table.