- hardy, stalwart, stout, sturdy - 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"
Antonym: frail (indirect, via robust)
- sturdy, tough - substantially made or constructed; "sturdy steel shelves"; "sturdy canvas"; "a tough all-weather fabric"; "some plastics are as tough as metal"
Antonym: delicate (indirect, via rugged)