Definitions:

1. a prominent status noun
   • The museum's grandness is well known around the world.
2. splendid or imposing in size or appearance noun
   • The grandness of the architecture impresses nearly everyone.
3. the quality of being magnificent or splendid or grand noun
   • The grandness of this building could be increased by adding some more tasteful ornamentation.
4. unusual largeness in size or extent or number noun
   • The grandness of this car is surprising.

Synonyms:

• enormousness
• greatness
• immenseness
• immensity
• importance
• magnificence
• sizeableness
• vastness
• wideness