gravity drive n.

He made a new ship…. It was equipped with gravity drive, and time distortion speed apparatus, and his far better trained mind finished this smaller ship with his titanic tools in less than the two days that it took them to reach Venone.

In a few minutes they were climbing into a long, slender winged cigar, equipped with gravity-drive.

None of them had ever built a rocketship, had ever seen one in action even. It was centuries obsolete in Galactic civilization. But gravity drives were out of the question. So—they’d had to design the ship from the ground up.

The ship settled to the vibrant thunder of the main gravity drive, which would be its prime mover until it was clear of the planetary system of which Onaris was part. Not until then could the cumbersome physical drive systems be abandoned in favor of the delicate subspace mechanisms which would flip the ship to its destination at mega[-]light velocities without regard to mass or momentum.

Obviously, we can now control gravity. Turn it on and off, change the direction, maybe reflect it—I’ve thought of lots of neat things you could do with gravity weapons and gravity drives on starships.

Heat shield, gravity drive, and life-support system had been sold off long ago. The former spaceship was crammed with loot, crawling with cats, and patrolled by pit bulls.