Synonyms for Grandness (same or very similar meaning)
WordNet sense 1 (a prominent status):
importanceWordNet sense 2 (unusual largeness in size or extent or number):
enormousness, greatness, immensity, vastness, wideness, immenseness, sizeablenessWordNet sense 3 (the quality of being magnificent or splendid or grand):
brilliance, grandeur, magnificence, splendor, splendourWordNet sense 4 (splendid or imposing in size or appearance):
impressiveness, richnessFrom the ODE community, based on WordNetadd/edit