Definition of sinister in US English:



  • 1Giving the impression that something harmful or evil is happening or will happen.

    ‘there was something sinister about that murmuring voice’
    • ‘Or did something more sinister happen, as Padilla's family and others fear?’
    • ‘The mutter of sinister threats and portents was already to be heard.’
    • ‘The Church is a dark and sinister place with creepy occult doings going on.’
    • ‘In a university, something even more sinister happens.’
    • ‘Only by unmasking a sinister conspiracy can he prove his innocence.’
    • ‘Whether in 2005 or 2025, we need a clearer picture of Cameroon, and less of a merely vague, sinister impression.’
    • ‘The high cheek bones are very pronounced, giving the creatures an impression of a continual sinister smile.’
    • ‘Strange and sinister things sometimes happen on the streets of York at the crack of dawn.’
    • ‘Noah's piece tends to show that neoconservatism is not the sinister conspiracy he thinks it is, not that neoconservatism is cracking up.’
    • ‘Norrell's love of secrecy and Strange's attraction to the wilder edges of magic invoke dark and sinister happenings.’
    • ‘Personally, I think it's all a sinister conspiracy by the BBC to overdub Doctor Who with something that has now spoilt it, to make us all buy it when it comes out on DVD.’
    • ‘Children across Bradford will be enjoying spooky shenanigans for Halloween tonight but police are urging that everyone takes care to make sure nothing more sinister happens.’
    • ‘Bound in the flayed skin of 100 saints and penned with the blood of virgins, this sinister and forbidden occult text is an item of incredible power.’
    • ‘A quick Google search reveals that several conspiracy web sites allege sinister motivations behind this conference.’
    • ‘It wasn't - there was no kind of sinister conspiracy at the start.’
    • ‘Nobody could say that anything sinister was happening.’
    • ‘Her early work gave way to more chilling visions that echoed fairy tale evils, sinister forests, cunning wolves, and grandmothers ready to eat you.’
    • ‘There is a worrying conviction growing in this community that something sinister is happening in our justice system.’
    • ‘Yet there are more sinister happenings afoot, as Count Dracula himself jumps into the mix, searching for a serum to make him invincible.’
    • ‘Not to be overlooked in the controversy were the paranoid prognosticators who saw grand conspiracies and sinister plots everywhere.’
    menacing, threatening, ominous, forbidding, baleful, frightening, eerie, alarming, disturbing, disquieting, dark, black, suggestive of evil, evil-looking
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    1. 1.1 Evil or criminal.
      ‘there might be a more sinister motive behind the government's actions’
      • ‘They are put into the custody of Count Olaf, a sinister villain who is plotting to steal their inheritance.’
      • ‘Judge Laity in England described the group as ‘corrupt, sinister and dangerous’.’
      • ‘Credit card fraud attracts sinister people who use the money to fund criminal activity such as terrorism.’
      • ‘Instead it's a candid admission he once lived the furtive lifestyle of a sinister international beer villain.’
      • ‘In many of his books, the heroes are noble trial lawyers while the villains are sinister corporations and the lawyers who agree to defend them.’
      evil, wicked, bad, criminal, corrupt, nefarious, villainous, base, vile, malevolent, malicious, malign
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  • 2Heraldry
    archaic attributive Of, on, or toward the left-hand side (in a coat of arms, from the bearer's point of view, i.e., the right as it is depicted).

    The opposite of dexter
    • ‘Each coat of arms has a right and left (i.e. dexter and sinister) heraldic side, as observed by the person carrying the shield.’


Late Middle English (in the sense ‘malicious, underhand’): from Old French sinistre or Latin sinister ‘left’.