Relating to or characterized by egoism; marked by excessive self-interest and self-centeredness.
From egoist (one who practices egoism) plus the suffix -ic, creating an adjective form meaning 'of or relating to egoism.'
Medieval monks used 'egoistic' as a serious spiritual insult—it meant you were basically damning your own soul by obsessing over yourself instead of God, which shows how much our moral vocabulary changes.
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