Open English Wordnet
Nouns
(n)slendernessthe quality of being slight or inadequate“he knew the slenderness of my wallet”, “the slenderness of the chances that anything would be done”, “the slenderness of the evidence”
(n)thinness, tenuity, slendernessrelatively small dimension through an object as opposed to its length or width“the tenuity of a hair”, “the thinness of a rope”