tough Synonyms

sturdy rugged hard stout toughened stern challenging knotty durable problematic difficult solid rough arduous severe robust vigorous ticklish thug thoroughpaced thorny thick-skinned vandal testing taut terrorist tenacious taxing uncompromising tight troubled unfeeling unbending tyrannical trying troublesome unsparing trojan tricky uphill tormenter valorous toilsome tiring tighter tiger thick swashbuckler stubborn steely