Answer:
Your answer doesn't provide that much evidence that much. But, I try to help you find the answer. I think your answer is the number of cycles per second perceived by the human ear. Well, Pitch is basically our sound of our voice. Sometimes, Our voice can even go 'higher' or 'lower'. Let me give you a example. If we screen our voice go higher than before and sometime it can even pitch. And, Sometime when we talk lower our voice give us a lower tune.
Good Luck!!~
By ♡Itsbrazts♡