Gloominary is a portmanteau of gloom and luminary. It means someone prominent who speaks only of how terrible things are, and who has no solutions that aren't worse than the problems they harp upon. Think Greta Thunberg (the Swedish "How dare you!" environmental activist), Al ("Inconvenient Truth") Gore, or Bernie ("Never had a real job") Sanders, and you'll have the essence of "gloominary" down pat. One can only cry wolf so long before oneself becoming the butt of jokes and before people simply stop listening.
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