Irene and Frederic Joliot-___, co-winners of the 1935 Nobel Prize in Chemistry (5)
I believe the answer is:
curie
(Other definitions for curie that I've seen before include "Scientist" , "Unit of radioactivity" , "Marie --, discoverer of Radium" , "Nobel Prize winner for physics (1903) and chemistry (1911), d. 1934" , "One of two Nobel prizewinners" .)