The term 'CERTAIN WAR HERO' can be broken down into three crossword solutions: ACE (3 letters). The term 'ACE' is a term used to describe an individual who is highly skilled in their field, and is often used to refer to a military pilot who has shot down a large number of enemy aircraft. In the context of a war hero, it could refer to a soldier who has performed exceptionally well in battle, or a pilot who has achieved a high number of successful missions.