Synonyms of insidious in English:

insidious


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See Spanish definition of insidioso

adjective

1‘the insidious erosion of rights and liberties’

SYNONYMS
stealthy, subtle, surreptitious, sneaking, cunning, crafty, Machiavellian, artful, guileful, sly, wily, tricky, slick, deceitful, deceptive, dishonest, underhand, backhanded, indirect
informal sneaky
ANTONYMS

straightforward