kingpin
n. C1 Advanced US //ˈkɪŋˌpɪn// UK //kˈɪŋpɪn// king·pin
n. the most important person or thing in a group. You use this to describe someone who has the most power or influence in a specific situation.
n. the most influential or powerful person in a group or organization. Often used in the context of criminal networks or high-stakes business environments.
He is the kingpin of the local music scene.
The police finally arrested the kingpin behind the entire smuggling operation after months of investigation.
While the board of directors provides the official oversight, the real kingpin of the corporation remains the CEO, whose personal vision dictates the company's strategic direction.
From king + pin.