Contraction. Contraction of why is. Why’s he doing that?

Why is it or why is it?

Originally Answered: Which is grammatically correct, “Why it is” or “Why is it”? Both are correct, depending on context. “Why is it?” is a question.

Why is meaning?

1 : the cause or reason for which We know why you did it. 2 : for which Here’s the reason why I did it.