Webster's Revised Unabridged Dictionary · 1913

Lightness

Lightness , noun

[From Light not heavy.]

The state, condition, or quality, of being light or not heavy; buoyancy; levity; fickleness; nimbleness; delicacy; grace.

Lightness , noun

[From Light bright.]

1.
Illumination, or degree of illumination; as, the lightness of a room. — Chaucer
2.
Absence of depth or of duskiness in color; as, the lightness of a tint; lightness of complexion.