Excessive self-love or self-importance; the practice of talking about yourself too much and thinking you're better than others.
From ego (Latin 'I') plus -tism (a suffix denoting a practice or system). The term became common in the 18th century as a criticism of excessive self-centeredness in social behavior and literature.
Egotism is the everyday word for self-centeredness that's been around since the 1700s, while egomania sounds more clinical and concerning—egotism is more about annoying behavior, egomania is about actual psychological obsession.
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