CPO Employer is an acronym for Chief Petty Officer Employer. This term is used to refer to a member of the United States Navy who is in charge of a division of enlisted personnel. The ENS in this crossword solution stands for Ensign, which is the lowest rank of commissioned officer in the U.S. Navy. The CPO Employer is responsible for the training and supervision of the Ensigns, as well as providing guidance and support to them.