Answer: tougher

AnswerCrossword Clue
TOUGHERMore durable
TOUGHERHarder to chew
TOUGHERMore difficult to chew
TOUGHERMore difficult.
TOUGHERHarder to crack
TOUGHERNot so easy
TOUGHERHarder to solve
toughersturdy
tougherdifficult
tougherunruly or rough
toughernot easily broken, cut, or chewed
tougherunyielding
tougherTOUGH, strong and resilient
tougherbrutal, lawless person