The quality or state of being extraordinary; the degree to which something is unusual, remarkable, or special.
From 'extraordinary' with the suffix '-ness' added to form an abstract noun expressing the quality or state. This is a productive pattern in English for creating nouns from adjectives.
The extraordinariness of ordinary things is what makes great literature—think of how Proust made a tea-dipped cookie reveal profound memories, or how the best movies find the remarkable hidden in everyday moments.
Complete word intelligence in one call. Free tier — 50 lookups/day.