Ne kadar sinsi bir varsayım.
- What an insidious assumption.
Bu çok sinsi bir hastalık. Çok geç olana kadar onu fark etmezsiniz.
- That's a very insidious disease. You don't notice it until it's too late.
Hansel and Gretel were lured by the witch's insidious gingerbread house.
The nurse always must be alert to signs of slow leak or insidious infiltration.