"I can't help it, I am not God!" the doctor answered offhand, though with the customary impressiveness.
"He'm not fled, Master Lionel," he announced with grim impressiveness. "He'm never a turntail.
And, obviously, due to the impressiveness of your claim, we would like to verify it with him.
the quality of making a strong or vivid impression on the mind: quality
splendid or imposing in size or appearance: stateliness, majesty, grandness, richness, expansivity, excellence, magnificence, loftiness, expansiveness