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egomaniac vs. narcissist

[ee-goh-mey-nee-ak, eg-oh-] / ˌi goʊˈmeɪ ni æk, ˌɛg oʊ- /

noun

  1. someone who displays egomania, a tendency to refer to oneself excessively and boastfully.

    Academic research appears to be a rat race of high-strung egomaniacs fighting over grant money, recognition, and their scientific legacies.

  2. someone who displays excessive selfishness and self-centeredness.

    Many have claimed that social media will turn us all into narcissists, egomaniacs, and internet addicts.

[nahr-suh-sist] / ˈnɑr sə sɪst /
Also narcist

noun

  1. a person who is overly self-involved, and often vain and selfish.

  2. Psychiatry. a person who has narcissistic personality disorder.

  3. Psychoanalysis. a person who experiences or exhibits narcissism, deriving erotic gratification from admiration of their own physical or mental attributes.