1. excessive concern with oneself; the practice of thinking only of one's own interests and ignoring the needs of others
Usage: common in everyday usage
2. in philosophy and ethics, the theory that self-interest is the proper basis for morality and that individuals should act in their own best interest
Usage: philosophical term

Examples

• His egoism prevented him from considering how his decisions affected his friends.
• The politician's egoism was evident in every speech he gave.
• Some philosophers argue that egoism is a valid ethical framework.
• Her egoism made it difficult for her to work well in team projects.
• The character's egoism was the main flaw that led to his downfall in the novel.
• Egoism and empathy are often seen as opposing forces in human behavior.