ion drive n.

Lifecraft 18 was a trim steel missile… It had its own ion drive, a regular crew of six, and plenty of additional space for our party.

He served for a year on one of the old ion-drive passenger lines, and he was quite sentimental about all ion-drive ships.

The ships are using the ion drive engine, which gives off a characteristic blue glow… The ion drive engine generates its power from nuclear energy.

Discussions…had already ruled out atomic power as inefficient and inadequate for achieving hyper-light speeds. Ion drive was ruled out for the same reasons.

The ion drive came to life. No man could have gone behind its thick shielding to watch it and survived.

Once they'd fallen a kilometre from the gateway, their ion drives came on, pushing them into high-inclination orbits which would provide coverage of the planet’s whole surface.

The H-shaped craft drew to a sudden halt above them, then began to descend.…One strut of the H contained the ion drive, and possibly its controlling AI—though such ships were usually telefactored—and crew quarters if necessary.