Main entry: tough, toughened
Definition: physically toughened
Usage: the tough bottoms of his feet
Antonyms: untoughened, tender
Definition: physically untoughened
Antonyms: soft
Definition: not protected against attack (especially by nuclear weapons)
Main entry: tempered, toughened, treated, hardened
Definition: made hard or flexible or resilient especially by heat treatment
Usage: a sword of tempered steel; tempered glass
Antonyms: unhardened, untempered
Definition: not brought to a proper consistency or hardness
Antonyms: incurable
Definition: incapable of being cured