Oscillation

Part of speech: noun (n.)

1. The act of oscillating; a swinging or moving backward and forward, like a pendulum; vibration.

2. Fluctuation; variation; change back and forth. His mind oscillated, undoubtedly; but the extreme points of the oscillation were not very remote. Macaulay. Axis of oscillation, Center of oscillation. See under Axis, and Center.