stdevp( ) appears to be mislabeled

[parisse]

I don't understand why someone would say standard deviation of population from population. Dividing by N is the normal definition of standard deviation, the one that should obviously be learned/teached first. Dividing by N-1 is a refinement, it requires more advanced students to be justified (and it does not have much impact if samples are of reasonable size). That justifies a shorter name for the straightforward definition and a longer one for the more advanced.
Excel and other spreadsheets may have different views, they are not math softwares, people using them are not expected to understand what standard deviation is.