What is the meaning of Oscillation?

the act of oscillating or the state of being oscillated

a regular periodic fluctuation in value about some mean

a single such cycle

defined for each point ${\displaystyle x}$ in the domain of the function by ${\displaystyle \inf \left\{\mathrm {diam} (f(U))\mid U\mathrm {\ is\ a\ neighborhood\ of\ } x\right\}}$, and describes the difference (possibly ∞) between the limit superior and limit inferior of the function near that point.

oscillation

an oscillation, a vibration, a shaking, a movement back and forth

an oscillation, a periodic variation

one cycle of such a variation

Source: wiktionary.org