= escape-pipe n. at escape, n.1 compounds.

Mechanics. An eduction valve; an exhaust valve. Obsolete.

A spout, mouthpiece, projecting aperture, or a short terminal pipe from which a jet of gas or liquid may issue or be discharged.

An aperture in a chamber or container for the passage of air, steam, or water; esp. one by which steam enters or exits the cylinder of a steam engine.

Steam-engine. The exit of steam from the cylinder after having done its work in propelling the piston; the passage through which this takes place; =…

A port (port, n.3 5a) in a steam engine. Now rare.