Either a Proton or a Neutron
This page is the CodyCross answer for the clue below from Casino, Group 269, Puzzle 1 (House Advantage).
Question is: Either a Proton or a Neutron
and the answer is: NUCLEON
Word Meaning:
NUCLEON — A proton (uud) or a neutron (udd).
Definitions from Wiktionary.