The word "ego" refers to a person's sense of self or identity. It is often associated with how individuals perceive themselves and their importance in relation to others. In psychology, the ego is considered a crucial part of the human personality, mediating between the desires of the id, the moral constraints of the superego, and reality. In a broader sense, people may use the term "ego" to describe someone's self-esteem or self-importance.
The term "ego" originates from Latin, where it means "I." It was adopted into English usage in the 19th century, particularly in psychological contexts.