sinister

adjective sin·is·ter \ˈsi-nəs-tər, archaic sə-ˈnis-\

: having an evil appearance : looking likely to cause something bad, harmful, or dangerous to happen

Full Definition of SINISTER

archaic : fraudulent

: singularly evil or productive of evil

a : of, relating to, or situated to the left or on the left side of something; especially : being or relating to the side of a heraldic shield at the left of the person bearing it

b : of ill omen by reason of being on the left

: presaging ill fortune or trouble

: accompanied by or leading to disaster

— sin·is·ter·ly adverb

— sin·is·ter·ness noun

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See sinister defined for kids

Origin of SINISTER

Middle English sinistre, from Anglo-French senestre on the left, from Latin sinistr-, sinister on the left side, unlucky, inauspicious

First Known Use: 15th century

Related to SINISTER

Synonyms: baleful, dire, direful, doomy, foreboding, ill, ill-boding, inauspicious, menacing, minatory, portentous, ominous, threatening

Antonyms: unthreatening

Synonym Discussion of SINISTER

sinister, baleful, malign mean seriously threatening evil or disaster. sinister suggests a general or vague feeling of fear or apprehension on the part of the observer <a sinister aura haunts the place>. baleful imputes perniciousness or destructiveness to something whether working openly or covertly <exerting a corrupt and baleful influence>. malign applies to what is inherently evil or harmful <the malign effects of racism>.

SINISTERNESS Defined for Kids