megalomania Syllabification: (meg·a·lo·ma·ni·a)Pronunciation: /ˌmegəlōˈmānēə/Translate megalomania | into German | into Italian Definition of megalomania noun obsession with the exercise of power, especially in the domination of others. delusion about one’s own power or importance (typically as a symptom of manic or paranoid disorder). Derivatives megalomanicPronunciation: /-ˈmanik/ adjective megalomania in other Oxford dictionaries Definition of megalomania in the British & World English dictionary