Synonyms of sinister in English:

sinister


See US English definition of sinister

See UK English definition of sinister

See Spanish definition of siniestro

adjective

1‘there was a sinister undertone in his words’

SYNONYMS
menacing, threatening, ominous, forbidding, baleful, frightening, eerie, alarming, disturbing, disquieting, dark, black, suggestive of evil, evil-looking
ill-omened, inauspicious, unpropitious, portentous
Scottish eldritch
informal spooky, scary, creepy
rare minatory, minacious, minatorial, bodeful, direful, sinistrous

2‘we need not assume a sinister motive for these meetings’

SYNONYMS
evil, wicked, bad, criminal, corrupt, nefarious, villainous, base, vile, malevolent, malicious, malign
underhand
informal shady
ANTONYMS

innocent, good