* doc/misc/calc.texi (Single-Variable Statistics): Fix the wording of
the documentation of the root mean square.
@kindex u R
@cindex Root-mean-square
@tindex rms
-Another commonly used mean, the RMS (root-mean-square), can be computed
-for a vector of numbers by using the @kbd{u R}
-(@code{calc-vector-rms}) [@code{rms}]command.
+The @kbd{u R} (@code{calc-vector-rms}) [@code{rms}]
+command computes the RMS (root-mean-square) of the data values.
+As its name suggests, this is the square root of the mean of the
+squares of the data values.
@kindex u S
@pindex calc-vector-sdev