# what is the difference between Standard error of the means vs Sampling error?

I am confused after learning about the different terms.

I understood Standard error of the means to be the Standard Deviation of the sample means, whilst Sampling error is the Standard Deviation within one sample

Am i understanding it correctly? Or have I oversimplified the comparisons or made a mistake in my understanding of the two concepts?

To demonstrate the distinction a little more clearly, consider a population that contains a single member with some characteristic C. Now imagine that you wish to measure the average C within this population. As the population only contains a single member, only one sample is possible, the sample that measures the single existing member. As such there can be no sampling error due to there being no choice in the sample to take.
Despite this it is still be possible to take repeated samples from this population, each of which could have its own unique 'measurement' error. As such these repeated measurements could produce differing estimates of C and as such have a standard error greater than 0.