meaning of lightness
1. The state, condition, or quality, of being light or not heavy; buoyancy; levity; fickleness; nimbleness; delicacy; grace.
2. Illumination, or degree of illumination; as, the lightness of a room.
3. Absence of depth or of duskiness in color; as, the lightness of a tint; lightness of complexion.
4. the visual effect of illumination on objects or scenes as created in pictures; "he could paint the lightest light and the darkest
">dark"