Ego' (3 letters) The crossword solutions for the term 'Vain Fellow' are FOP and EGO. A FOP is a person who is overly concerned with his own appearance and manners, often to the point of being considered conceited or arrogant. The word 'EGO' is derived from Latin and Greek and is used to refer to a person's sense of self-importance or self-esteem. In this context, the term 'Vain Fellow' can be used to describe someone who is excessively proud of their own accomplishments and appearance.