The quality of being round or curved.
Roundednesses can make things look smooth and soft.
Examples:
The roundednesses of the baby's cheeks were adorable.
The roundednesses of the hills made the landscape beautiful.
I like the roundednesses of the pebbles on the beach.
The roundednesses of the clouds made them look like fluffy pillows.
The roundednesses of the ball made it perfect for rolling.
The roundednesses of the vase made it look elegant.