Consular officer

按照INA 101(a)(9) The term "consular officer" means any consular, diplomatic, or other officer or employee of the United States designated under regulations prescribed under authority contained in this chapter, for the purpose of issuing immigrant or nonimmigrant visas

在移民法的语境下，CO就是使领馆的面试官，以及审批你的签证的人（包括不面试但是参与审批工作的人）