Available Definitions:
1) n. - The state, condition, or quality, of being light or not heavy; buoyancy; levity; fickleness; nimbleness; delicacy; grace.
2) n. - Illumination, or degree of illumination; as, the lightness of a room.
3) n. - Absence of depth or of duskiness in color; as, the lightness of a tint; lightness of complexion.