second-in-command
noun [ S ] uk/ˌsek.ənd.ɪn.kəˈmɑːnd/ us/ˌsek.ənd.ɪn.kəˈmænd/
副手;二把手
someone who is almost as important as the person in charge
Well, if the manager isn't available I'd like to speak to the second-in-command. 好吧,如果经理不在,我想和二把手谈谈。