IPA: /ˈɡreɪtnəs/
KK: /ˈɡreɪtnəs/
The quality or state of being very large, important, or impressive.
The greatness of her achievements inspired many people.
Greatness → It is formed from "great" (from Old English *grēat*, meaning large or big) and "-ness" (meaning the state or quality of). The word "greatness" refers to the state of being large or significant in size, quality, or importance.
Think of 'great' meaning large or significant, and remember that 'greatness' is the state of being large or significant.