slimness
noun /ˈslɪmnəs/
  /ˈslɪmnəs/
[uncountable]- the quality of being thin, in a way that is attractive synonym slenderness (1)- Her slimness and refined features make her unusually elegant.
 
- the quality of being thinner than usual- The new slimness of the machine makes it even more portable.
 
- the fact of being smaller than you would like or expect synonym slenderness (3)- The slimness of his party's majority may not be enough to keep him in power.