Intransitive verb. 1)The specific ability to perform adeptly a style of rock music which includes guitars, drums, and a blues influence. 2)To surpass all contenders in excellence, ability, or fame. 3) To render all viewers speechless at one's excellence, ability, or fame.
Music. "The vintage vinyl of Bad Company that my dad gave me rocks hard."
Excellence. "Congratulations on that summa cum laude! You really rock hard, Michelle!"
Ability. "Our band really rocked hard last night, didn't it?"
Fame. "The Beatles rocked hard."