HEADWAY

headway, head

(noun) forward movement; “the ship made little headway against the gale”

headroom, headway, clearance

(noun) vertical space available to allow easy passage under something

Source: WordNet® 3.1

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Etymology

Noun

headway (countable and uncountable, plural headways)

Movement ahead or forward.

(nautical) Forward motion, or its rate.

(countable, transport) 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.

(uncountable, figuratively) Progress toward a goal.

(countable) The clearance beneath an object, such as an arch, ceiling or bridge; headroom.

(coal-mining) A cross-heading.

Source: Wiktionary

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Head"way`, n.

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

2. (Arch.)

Definition: Clear space under an arch, girder, and the like, sufficient to allow of easy passing underneath.

Source: Webster’s Unabridged Dictionary 1913 Edition

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