IPA: /ˈnʌmɪŋli/
KK: /ˈnʌmɪŋli/
In a manner that causes a loss of feeling or awareness.
The movie was so long that it felt like it was dragging on numbingly.
Numbingly → It is formed from "numb" (from Old English "numen", meaning to make numb or to lose feeling) and "-ly" (a suffix meaning in a manner of). The word "numbingly" describes the manner in which something causes a loss of feeling or sensation.
Think of the word 'numb' which means to lose feeling, and remember that 'numbingly' describes doing something in a way that causes a loss of sensation.