noun. Forward movement or the rate of forward movement, especially of a ship.

noun. Progress toward a goal.

noun. The clear vertical space beneath a ceiling or archway; clearance.

noun. The distance in time or space that separates two vehicles traveling the same route.

noun. In railroading, the. time which elapses after one train passes a certain point before the following train passes that point.

noun. Motion ahead or forward; force or amount of such motion; rate of progress: said specifically of a ship, but applied to all kinds of progress, literally or figuratively.

noun. In architecture, clear space in height, as from a floor to a ceiling, or from the ground to the crown of an arch; specifically, the perpendicular distance from any step or landing of a stair to the ceiling.

noun. In coal-mining, a cross-heading.

noun. The progress made by a ship in motion; hence, progress or success of any kind.

noun. Clear space under an arch, girder, and the like, sufficient to allow of easy passing underneath; clearance; headroom.

noun. Movement ahead or forward.

noun. Forward motion, or its rate.

noun. The interval of time or distance between the fronts of two vehicles (e.g. buses) moving in succession in the same direction, especially along the same pre-determined route.

noun. Progress toward a goal.

noun. The clearance beneath an object, such as an arch, ceiling or bridge; headroom.

noun. A cross-heading.

noun. forward movement

noun. vertical space available to allow easy passage under something

"Actually, while it seems counterintuitive, frequent headway is critical to changing behavior on a more permanent basis."

seaway  to fetch headway  

make headway  

advance  elbowroom  progress  progression  room  

impetus  inroads  tighten  weaken  widen  

Great Leap Forward  advance  advanced  advancement  advancing