oscillation

n. act of something which oscillates; regular pendulation between two positions; vacillation between two opinions; fluctuation between high and low values; wavering between two extremes

For other uses, see oscillator (disambiguation) Oscillation is the variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. Familiar examples include a swinging pendulum and AC power. The term vibration is sometimes used more narrowly to mean a mechanical oscillation but sometimes is used to be synonymous with "oscillation." Oscillations occur not only in physical systems but also in biological systems and in human society.
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Noun
1. the process of oscillating between states
(hypernym) natural process, natural action, action, activity
(hyponym) libration
(derivation) hover, vibrate, vacillate, oscillate
2. (physics) a regular periodic variation in value about a mean
(synonym) vibration
(hypernym) wave, undulation
(hyponym) ripple
(derivation) oscillate, vibrate
(classification) physics, physical science, natural philosophy
3. a single complete execution of a periodically repeated phenomenon; "a year constitutes a cycle of the seasons"
(synonym) cycle
(hypernym) periodic event, recurrent event
(hyponym) cardiac cycle
(derivation) oscillate, vibrate

n. swaying, rocking, sway, wavering, oscillation

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

(n.)
Fluctuation; variation; change back and forth.