The quality or state of being fanciful; the characteristic of being imaginative, whimsical, or impractical.
From 'fanciful' plus the noun-forming suffix '-ness.' This creates an abstract noun that describes the degree to which something exhibits imaginative or whimsical qualities.
The more suffixes you stack—fancy → fanciful → fancifulness—the more abstract the word becomes, which is how language lets us talk about not just things but ideas about things!
Complete word intelligence in one call. Free tier — 50 lookups/day.