a prophet of doom
prophet of doom
A person who always warns others about possible negative consequences of decisions or actions. Don't tell Rodney about your new plan—he's such a prophet of doom that he'll completely kill your motivation.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
a ˌprophet of ˈdoom,
a ˈdoom merchanta person who always expects that things will go very badly: Various prophets of doom have suggested that standards in education are worse than ever.
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