Light Bulb Containing Iodine
Puzzle 5 of Expensive foods Medium Pack
Question is: Light Bulb Containing Iodine
and the answer is: HALOGEN
Word Meaning:
HALOGEN — (chemistry) Any element of group 17, i.e. fluorine, chlorine, bromine, iodine, astatine and tennessine.
Definitions from Wiktionary.