adjective see: sit Date: 1545 1. awaiting a chance to entrap ; treacherous , harmful but enticing ; seductive , 2. having a gradual and cumulative effect ; subtle , developing so gradually as to be well established before becoming apparent, ~ly adverb ~ness noun
INSIDIOUS
Meaning of INSIDIOUS in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012