Of, exhibiting, or affected with megalomania(adjective)
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Use "megalomaniacal" in a sentence
"When people look at me and say "megalomaniacal" - why the inflection, as if it were a bad word?"
"These people were ready to betray their country, not for money but in a kind of megalomaniacal pride in what they - they themselves - were going to achieve for that country."
"Interestingly, the museum exists to stand as a force against exactly this kind of megalomaniacal, controlling thinking."