Definition of turnpiker:
(n) :
(chiefly US) A toll road, especially a toll expressway.
(n) :
A gate or bar set across a road to stop carriages, animals, and sometimes people, until a toll is paid.
(n) :
A frame consisting of two bars crossing each other at right angles and turning on a post or pin, to hinder the passage of animals, but admitting a person to pass between the arms.
(n) :
(military) A beam filled with spikes to obstruct passage; a cheval de frise.
(n) :
(Scotland) A winding stairway.
(n) :
(mathematical economics) A trajectory on a finite time interval that satisfies an optimality criterion which is associated with a cost function.