sturdy in WordNet English dictionary

1. having rugged physical strength; inured to fatigue or hardships
   "hardy explorers of northern Canada"; "proud of her tall stalwart son"; "stout seamen"; "sturdy young athletes"
   hardy  stalwart  stout  sturdy 
   
2. not making concessions
   "took an uncompromising stance in the peace talks"; "uncompromising honesty"
   uncompromising  sturdy  inflexible 
   
3. substantially made or constructed
   "sturdy steel shelves"; "sturdy canvas"; "a tough all-weather fabric"; "some plastics are as tough as metal"
   sturdy  tough