What is the difference between standard error of sample mean and sample standard deviation?

Standard error

A statistical measure of the dispersion of a set of values. The standard error provides an estimation of the extent to which the mean of a given set of scores drawn from a sample differs from the true mean score of the whole population. It should be applied only to interval-level measures.

Standard deviation

A measure of the dispersion of a set of data from its mean. The more spread apart the data is, the higher the deviation,is defined as follows:

Standard error x sqrt(n) = Standard deviation

Which means that Std Dev is bigger than Std err

Also, Std Dev refers to a bigger sample, while Std err refers to a smaller sample