(n.) The quality or state of being prodigious; the state of having qualities that excite wonder or astonishment; enormousness; vastness.

ampleness amplitude awesomeness beguilingness boundlessness bulk enchantingness enormity enormousness enticingness exceptionality expanse extraordinariness fabulousness fascination formidableness fullness gigantism glamorousness grandeur grandness great scope greatness hugeness immensity impossibility inconceivability incredibility increditability infinity intensity largeness magnitude marvelousness might mightiness miraculousness monstrosity monstrousness muchness mysteriousness mystery mythicalness numinousness phenomenalness plenitude power rareness rarity remarkableness seductiveness strength stupendousness tremendousness uncommonness uniqueness unordinariness unusualness unwontedness vastness wonderfulness wondrousness