Radioactive metallic element (6)
'radioactive metallic element' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for uranium that I've seen before include "Radoactive element" , "Fissile element" , "Radioactive element of atomic number 92" , "Radioactive metal used as fuel in nuclear reactors" , "Chemical element, source of nuclear energy" .)
'radioactive metallic element' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for radium that I've seen before include "Radioactive element discovered by the Curies" , "Metallic element discovered by the Curies" , "Chemical element, Ra" , "Element with symbol Ra" , "Ra (atomic number 88)" .)