One of my favorite terms from Golden Age science fiction is the idea of from Crashing Suns by Edmond Hamilton, published by Popular Fiction Publishing Co. in 1928:

He had travelled the space-lanes of the solar system for the greater part of his life, and now all of his time-honored rules of interplanetary navigation had been upset by this new cruiser.

The idea of "space lanes" seems clear; the term is analogous to "sea lanes", the well-trafficked courses that merchant ships take from one port to another. However, since the various bodies of the solar system are in constant motion relative to each other, and since the entire solar system itself is moving through space around the center of the galaxy, which is itself moving through space, the idea of static space-lanes seems unworkable. But it's a great concept for story writing.

Another instance can be found in the excellent 1934 short story Cosmic Teletype by Carl Jacobi. Jospeph Rane, injured during college and missing part of his brain, turned what was left to scientific pursuits. He succeeded in constructing a device able to contact inhabitants of distant worlds.

The messages were in code; but once translated, they revealed an entire civilization at war.

General emergency report. Dromeda, daughter of Calian and most beautiful woman in all Lirius was kidnapped early today by a man thought to be Tarana, son of the king of Uranus. It is believed that Tarana arrived secretly on Lirius on a space ship, traveling out of patrolled space-lanes. A council of war will be held immediately.

A decade later, this expression was in common usage; here's an example from One Against the Legion (1939) by Jack Williamson:

A tiny ship, however, was now driving outward from the sun, parallel to the ecliptic plane and two hundred million miles beyond the limits of the space-lanes.

By the 1950's, this phrase had become a cliche. Take a look at this ironic excerpt from Philip K. Dick's short story Sales Pitch:

Commute ships roared on all sides, as Ed Morris made his way wearliy home to Earth at the end of a long hard day at the office. The Ganymede-Terra lanes were choked with exhausted, grim-faced businessmen; Jupiter was in opposition to Earth and the trip was a good two hours. Every few million miles the great flow slowed to a grinding, agonized halt; signal-lights flashed as streams from Mars and Saturn fed into the main traffic-arteries.

A similar term is "spaceways", first used in Shambleau, by C.L. Moore, published by Weird Tales in 1933:

He heard the gossip of the spaceways, news from a dozen planets of a thousand different events...

This helpful word found itself into many breezy statements about space. For example, this usage in The Impossible World (1939) by Eando Binder:

Shelton was shaking his head. It always hurt to hear of brave men meeting doom out in the spaceways — young, spirited men who had much to live for. Some of them were important, too; scientists, technicians. Now they were martyrs to mankind’s steady march toward complete dominion of the Solar System.

Here's another example from Jurisdiction (1941), by Nat Schachner:

The Erebus was the luxury liner of the spaceways.

From Sunward Flight (1943) by Leo Zagat:

...more than one rocketeer has been known to crack up, mentally, on the spaceways. The grueling flights through blackness are murderous.

From The Cavern of the Shining Pool (1943) by Leo Zagat:

...they had leaped to send warning of the one unconquered menace that harried the spaceways. An ether eddy!

From Contagion (1950) by Katherine MacLean:

Therefore spaceways and interplanetary health law demanded that ship equipment for guarding against disease be totally mechanical in operation, rapid and efficient.