Extremely hardworking or demanding
Having a strong, fast-paced beat.
Having rugged physical strength; inured to fatigue or hardships.
Impudent.
Able to survive adverse growing conditions.
Brave and resolute.
Anything, especially a plant, that is hardy.
A blacksmith's fuller or chisel, having a square shank for insertion into a square hole in an anvil, called the hardy hole.