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sinister

adj.
US //ˈsɪnɪstɝ// UK //sˈɪnɪstɐ// sin·is·ter
  1. 1 evil or threatening (adj.)
    B2 Upper Intermediate

    giving the impression that something evil or harmful is happening or will happen.

    suggesting or threatening evil, harm, or trouble. Often used to describe an atmosphere, a person's expression, or a mysterious event.

    Example

    There was a sinister figure standing in the shadows at the end of the street.

    Example

    The abandoned mansion had a sinister atmosphere that discouraged even the most curious teenagers from approaching its gates after dark.

  2. 2 heraldry / left side (adj.)
    C2 Proficiency Technical Archaic

    relating to the left side of a shield or coat of arms.

    pertaining to the left side of a heraldic shield from the perspective of the bearer, which appears as the right side to the observer.

    Example

    The knight's shield featured a red stripe on the sinister side.

    Example

    The genealogist noted a bend sinister on the family crest, a traditional heraldic mark often associated with illegitimate lineage.

    Usage

    In heraldry, 'sinister' is the opposite of 'dexter'.

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  1. 3 dishonest or corrupt (adj.)
    C1 Advanced Literary Formal

    dishonest or sneaky in a way that is hard to see.

    characterised by deviousness, dishonesty, or underhanded motives. This sense is less about physical threat and more about moral corruption.

    Example

    The politician had a sinister plan to win the election by cheating.

    Example

    The investigation uncovered a sinister plot to embezzle funds from the charity through a series of complex offshore accounts.

Origin

From Middle English sinistre (“unlucky”), from Old French senestre, sinistre (“left”), from Latin sinister (“left hand”).

Idioms1 entry

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