chief executive
noun [ C usually singular ] uk/ˌtʃiːf ɪɡˈzek.jʊ.tɪv/ us/ˌtʃiːf ɪɡˈzek.jə.t̬ɪv/
（公司或机构的）首席执行官，总裁
the person with the most important position in a company or organization
She's the chief executive of one of the country's largest charities. 她是该国最大的慈善组织之一的首席执行官。
Chief Executive 美国总统
the president of the United States
All five Chief Executives who have run for re-election during a war have won, including Bush. 五位在战争期间竞选连任的美国总统都获胜了，包括布什。