WordWeb Online

1. Relatively small dimension through an object as opposed to its length or width
   "the tenuity of a hair";
   - thinness, slenderness
    
2. A rarified quality
   "the tenuity of the upper atmosphere";
   - rarity, low density
    
3. The quality of lacking intensity or substance
   "a shrill yet sweet tenuity of voice";
   - feebleness

Derived forms: tenuities

Type of: denseness, density, dimension, weakness

Antonym: thickness