A freeway that is part of the Interstate Highway System.
Of, or relating to two or more states.
Crossing states (usually provincial state, but also e.g. multinational sense).
A toll road, especially a toll expressway.
A trajectory on a finite time interval that satisfies an optimality criterion which is associated with a cost function.
A gate or bar set across a road to stop carriages, animals, and sometimes people, until a toll is paid,
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; a turnstile.
A beam filled with spikes to obstruct passage; a cheval de frise.
A winding stairway.
To form (a road, etc.) in the manner of a turnpike road, or into a rounded form, as the path of a road.