Radium discoverer (5,5)
'radium discoverer' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for curie that I've seen before include "Marie --, French chemist" , "measure of radioactivity" , "Unit of radioactivity" , "One of two Nobel prizewinners" , "Marie --, discoverer of Radium" .)