1535-45; < Latin insidiōsus deceitful, equivalent to insidi (ae) (plural) anambush (derivative of insidēre to sit in or on) + -ōsus -ous; see sit1
The greatest dangers are the most insidious. Seemingly benign.
And people often tend to believe what it suits them to believe.
And by which people do or spread 'evil' in the deluded name of 'good'.
what else?
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