1. nonmetallic crystalline halogen element: a poisonous, dark gray to purple-black, lustrous, nonmetallic crystalline element in the halogen family. Source: brine. Use: germicide, antiseptic, preparation of dyes, pharmaceuticals, tinctures, isotopes in medicine and industry. Symbol I
2. antiseptic: a mixture of iodine solution and potassium iodide in alcohol. Use: topical antiseptic.
[Early 19th century. < French iode< Greek iōdēs "violet-colored" < ion "violet"]
