WordWeb Online

1. Of or relating to or forming or attached to a skeleton
   "the skeletal system"; "skeletal bones"; "skeletal muscles"
    
2. Very thin especially from disease, hunger or cold
   "a nightmare population of gaunt men and skeletal boys";
   - cadaverous, emaciated, gaunt, haggard, pinched, wasted

See also: lean, meager [N. Amer], meagre [Brit, Cdn], thin

Encyclopedia: Skeletal