(1):

(n.) A hook or pin on which a rudder hangs and turns.

(2):

(n.) The pivot pin of a hinge.

(3):

(n.) An upright pivot pin

(4):

(n.) A little pin.

(5):

(n.) A kingbolt of a wagon.

(6):

(n.) A pivot about which the chassis swings, in some kinds of gun carriages.