delusions of grandeur

/D IH0 L UW1 ZH AH0 N Z AH1 V G R AE0 N D UW1 R/
noun
  1. 1

    (usually plural) The false belief that one is important or powerful, accompanying certain mental disorders.

  2. 2

    (usually plural) Conceitedness or overconfidence.

Synonyms

Source: https://en.wiktionary.org/wiki/delusion%20of%20grandeur, https://en.wiktionary.org/wiki/delusions%20of%20grandeur