An alter ego is a second self, often used to describe a person's different or opposite personality. It can also be used to refer to a close FRIEND or CONFIDANT. The crossword solutions for the term ALTER EGO include OTHER (5 letters), FRIEND (6 letters), CONFIDANT (9 letters), PAL (3 letters), PARTNER (7 letters), MATE (4 letters), HYDE (4 letters), BAT (3 letters), and ALIAS (5 letters). These words all refer to someone who is close to the person, and can be used to describe an alter ego.