meg ‧ a ‧ lo ‧ ma ‧ ni ‧ ac /ˌmeɡ ə ləʊˈmeɪniæk $ -loʊ-/ BrE AmE noun [countable]
someone who wants to have a lot of power for themselves and enjoys having control over other people’s lives
—megalomaniac adjective
meg ‧ a ‧ lo ‧ ma ‧ ni ‧ ac /ˌmeɡ ə ləʊˈmeɪniæk $ -loʊ-/ BrE AmE noun [countable]
someone who wants to have a lot of power for themselves and enjoys having control over other people’s lives
—megalomaniac adjective
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012