Wiktionary
adv. In a way or to an extent that numbs
Usage examples of "numbingly".
It threw him numbingly against the rocks, then hurtled him back into the swift-flowing current.
Sarasper sprang into the air, to make the force of his blow as numbingly heavy as possible, and brought the keelpin down.
The weapon seemed to leap and then hum numbingly in his hands, and Dauneth almost dropped it, but around him the smokelike thing seemed to be shuddering and fading all at once.
The flip side might be logical chaos--a verdict or the absence of a verdict spawned by the numbingly protracted cross-media extravaganza that has deluged all would-be jurors and indeed the entire American public with an accretion of contradictory details both densely pertinent and superfluous--a huge shitstorm of information, misinformation, innuendo, and disingenuously reported rebop that backs you into a corner like a date rapist you can never escape until you shut down your electronic and printed-page access to the world, move to the South Pole, and start flicking penguins.