A person who is excessively self-centered and believes their own interests are more important than those of others.
From the French 'égoïste,' derived from Latin 'ego' (I). The philosophical term became a social label in the 19th century for people perceived as selfish.
Egoism is actually a philosophical position (not just a personality flaw)—Max Stirner argued that rational self-interest is moral—but the word 'egoist' today almost always means someone unpleasantly selfish, showing how moral judgment sneaks into supposedly neutral labels.
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