WordWeb Online

1. Having rugged physical strength; inured to fatigue or hardships
   "sturdy young athletes";
   - hardy, stalwart, stout
    
2. Not making concessions
   "took a sturdy stance in the peace talks";
   - uncompromising, inflexible
    
3. Substantially made or constructed
   "sturdy steel shelves"; "sturdy canvas";
   - tough

Derived forms: sturdier, sturdiest

See also: hardline, hard-line, robust, rugged