The term 'ATOM' is a four-letter solution to the crossword for the cartoon superhero 'ANT'. The ATOM is a DC Comics superhero created by Julius Schwartz, Gardner Fox and Gil Kane. He first appeared in Showcase #34 in October 1961. The ATOM is the alter ego of Ray Palmer, a professor of physics at Ivy University. He has the ability to shrink himself down to subatomic size and can control his density. He also has superhuman strength and agility.