In the meeting room, he acts like the alpha-dog, everyone follows his lead.

alpha-dog 由 alpha（希腊字母表的第一个字母，引申为"首要的"或"主导的"）和 dog（狗）组成。 alpha-dog 字面意思是"领头狗"，在群体中处于支配地位的狗。引申为"领导者"或"主导者"，指在某个群体中占据主导地位的人。