kingpin vs influential person

kingpin and influential person both are nouns.

Word	Noun	Adjective	Verb	Adverb
kingpin	Yes	No	No	No
influential person	Yes	No	No	No

As nouns, influential person is a hypernym of kingpin; that is, influential person is a word with a broader meaning than kingpin:

kingpin: the most important person in a group or undertaking
influential person: a person whose actions and opinions strongly influence the course of events

Other hypernyms of kingpin include important person, personage.

kingpin (noun)	influential person (noun)
bolt that provides a steering joint in a motor vehicle	a person whose actions and opinions strongly influence the course of events
the front bowling pin in the triangular arrangement of ten pins
the most important person in a group or undertaking