$n$th root of $x$ - technical term for $n$?

Question

As you can see in the title, I want to know how the number before a root is called.

For example, if you have the cubic root of 8, I want to know how the 3 before the roof is called.

Actually, I already know it - but in German... In German, it's called "Wurzelexponent".

If I translate that german eord into English, it is "root exponent". Is that correct?

Thank you.

Answer 1

The most common term I've seen for $n$ in the expression $\sqrt[n]{x}$ is the index, or root index.

Wikipedia's article on $n$th roots mentions this, but only twice (for the first time in the third paragraph of the page).

Answer 2

n is called the order of the root, since the expression is “the root of order n”.