Русско-англо-русский юридический словарь

Separation from employment may result from resignation, retirement, layoff, completion of a time-limited appointment, non-renewal of an employment contract, or discharge. (Mississippi State University)

An employer can say that there is a separation of employment instead of using the words "terminate" or "fire." Although it still means that the employee no longer works for the employer, it does not sound as harsh or carry the negative connotations for the employee. (CHRON)