26 sinister synonyms include menacing, threatening, ominous, forbidding, baleful, frightening, eerie, alarming, disturbing, and disquieting. Sinister is an adjective, and its antonyms are benevolent and kind. Here are some additional synonyms for "sinister" with example sentences.
26 other ways to say sinister.
A sinister shadow loomed in the dark hallway.
He gave a sinister smile that sent chills down my spine.
The abandoned house had a sinister atmosphere.