The best replacement for circular motion is linear motion.

The best alternatives to circular motion are rated as following:
★★★★★  linear motion
★★★★  rotational motion
★  simple harmonic motion

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Speaking about circular motion, one probably shouldn't forget about tension.

Other search terms related to circular motion and their ratings are:
★★★★★ tension
You have in mind a companion for circular motion and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of circular motion in all years. Click on graph for more.
circular motion
linear motion
rotational motion