SLIGHTNESS
slenderness, slightness, slimness
(noun) the property of an attractively thin person
delicacy, slightness
(noun) smallness of stature
pettiness, triviality, slightness, puniness
(noun) the quality of being unimportant and petty or frivolous
Source: WordNet® 3.1
Etymology
Noun
slightness (plural slightnesses)
The property of being slight, smallness, petiteness
Poor nutrition explained his slightness.
Source: Wiktionary
Slight"ness, n.
Definition: The quality or state of being slight; slenderness; feebleness;
superficiality; also, formerly, negligence; indifference; disregard.
Source: Webster’s Unabridged Dictionary 1913 Edition