kingpin

1. The axis around which steered wheels pivot; a bolt that holds the axis in place—a kingbolt.
2. The pivot or connector between a tractor and trailer in the fifth-wheel coupling of semi-trailer truck.
3. (informal) The most important person in a usually evil undertaking or organization, often a druglord.
4. The pin at the centre of the triangle of bowling pins (originally the tallest pin in kayles). Sometimes also the headpin at the apex.
5. The bolt holding together the truck of a roller skate or skateboard.

Pronounced as (IPA)

/ˈkɪŋ.pɪn/

Etymology

From king + pin.

Synonyms

kingbolt

headpin

swivel pin

bigwig

top banana

boss

center pin

pintle

pivot

supremo

top dog

big fish

centrepin

drug lord

drug baron

coupling bolt

core pin

king bolt

roller pin

king pin

master pin

main pin

corepin

quill roller

Pomo

rolling needle

chief

guvnor

head

leader

linchpin

old man