imperceptibly

Researchers have developed a method to make adaptive and eco-friendly sensors that can be directly and imperceptibly printed onto a wide range of biological surfaces, whether that's a finger or a flower petal.

The lieutenant nodded almost imperceptibly at my robes.

In the corner of her eye she noticed Kat almost imperceptibly shaking her head no.

But then, as Nick sauntered away, making it almost imperceptibly clear that he would never follow up, I finally accepted it.

Trees put down roots and grow so slowly and imperceptibly that you can’t really notice.