D defs.my
Entry 2 senses Webster, 1913

Oscillate

/(ŏs"sĭl*lāt)/ · Os·cil·late · IPA /ˈɑsɪleɪt/
01 v. i. To move backward and forward; to vibrate like a pendulum; to swing; to sway.
imp. & p. p. Oscillated; p. pr. & vb. n. Oscillating
  1. 1.
    To move backward and forward; to vibrate like a pendulum; to swing; to sway.
  2. 2.
    To vary or fluctuate between fixed limits; to act or move in a fickle or fluctuating manner; to change repeatedly, back and forth.
    “The amount of superior families oscillates rather than changes, that is, it fluctuates within fixed limits.” De Quincey.