List of Radioactive Elements in the Periodic Table
Puzzle 15 of Fabric Arts Medium Pack
Question is: List of Radioactive Elements in the Periodic Table
and the answer is: ACTINIDE
Word Meaning:
ACTINIDE — Any of the 15 radioactive elements of the periodic table from actinium to lawrencium that are positioned under the lanthanides, to which they have similar chemistry.
Definitions from Wiktionary.