What did Ra mean by...?

[moyal]

In the German version 'power' is translated as mathematical 'Potenz' (=Exponentiation).

From wikipedia:

The exponent is usually shown as a superscript to the right of the base. In that case, b^n is called "b raised to the n-th power", "b raised to the power of n", or "the n-th power of b".

-> https://en.wikipedia.org/wiki/Exponentiation