kingpin
(noun)
noun
1. the most important person in a group or undertaking
Similar word(s): bigwig
Definition categories: person, personage
2. bolt that provides a steering joint in a motor vehicle
Similar word(s): kingbolt
Definition categories: man–made, bolt
3. the front bowling pin in the triangular arrangement of ten pins
Similar word(s): headpin
Definition categories: man–made, pin