Hard as balls
Very tough. Said of a person nobody would want to cross.
I wouldn't start on him, he's hard as balls so he is.

Shall I translate it into posh English for you, mucker?
Ah, a person of taste, I see. Here it is in posh English.
I should not provoke him. He is exceptionally tough.
Questions
What does hard as balls mean in Ireland?
Very tough. Said of a person nobody would want to cross.
How do you use hard as balls in a sentence?
“I wouldn't start on him, he's hard as balls so he is.”
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