1. an intensely radioactive metallic element that occurs in minute amounts in uranium ores • Syn: radium, atomic number 88 • Hypernyms: metallic element, metal • Substance Holonyms: uranium ore 2. ancient Egyptian sun god with the head of a hawk; a universal creator; he merged with the god Amen as Amen-Ra to become the king of the gods • Syn: Re • Topics: antiquity • Instance Hypernyms: Egyptian deity