as, air-line road.

See also: Air

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in classic literature ?
When unusual needs arose for them, such as the building of the great highways and air-lines, of canals, tunnels, subways, and fortifications, levies were made on the labor-ghettos, and tens of thousands of serfs, willy-nilly, were transported to the scene of operations.
Durapipe UK has provided its specialist compressed air distribution pipework system, Air-Line Xtra for an expansion project at Glendon Products.
Air-Line Xtra was specified to convey compressed air from the ring main system to the pneumatic machinery within the new factory.
Durapipe Air-Line Xtra provided a suitable product for this job as the smooth internal bore of the product prevents scale build up to ensure the air is kept clean and uncontaminated for the lifetime of the product.
Brian Leach, director of Glendon Products comments: "We specified Air-Line Xtra due to the ease of installation it provides and because we didn't need to employ a specialist contractor, it not only offered a cost effective option but also flexibility for future expansions.
"Most importantly, Air-Line Xtra ensures that the compressed air is kept clean and uncontaminated which is paramount for Glendon Products."
NSTM says: "On board submarines, the officer in charge of the control room (officer of the deck) and the officer in charge of the maneuvering station (engineering officer of the watch), diving officer of the watch, and chief of the watch shall have air-line masks with annunciators available for use.
This situation can be changed if an air-line interface (similar to a 3.5 mm connector interface) is used instead of the fully dielectric-loaded SMA line.
Another advantage of an air-line interface is that the reduction in the body bore diameter improves the mechanical properties of the connector because of the increased thickness of the male connector outer conductor (one of the main weaknesses of the standard SMA connector).
Implementation of this air-line interface makes it possible to design high power Fluoroloy H-loaded connectors and adapters.
An infinite number of the air-line interfaces are available, which are mechanically and electrically compatible to the SMA interface, but a 3.2 mm air line is convenient for a Fluoroloy H-loaded cable connector and adapter because a one-piece contact can be used (this is important for high power applications).
With the air-line interface, heat is not conducted in the transverse direction from the inner conductor to the body because there is no dielectric and air is a poor thermal conductor.