A person who practices egotism; someone who is self-centered, talks about themselves too much, and thinks they're better than others.
From egotism plus the agent suffix -ist (one who practices). This term has been used since the 18th century to describe people whose behavior and speech is dominated by self-interest and self-praise.
An egotist is that person who turns every conversation back to themselves and genuinely seems to believe they're the most important person in the room—it's the person form of the behavior, and the word has been calling out this type for 300 years.
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