EEG amplifier circuit low and high pass filters. Oscillations, noise, etc
"Oscillation frequency" is a term that describes the frequency where the input-output phase relationship is exactly zero degrees i.e. if this filter were part of a circuit used as an oscillator it would oscillate at this frequency. Sometimes oscillation frequency is quoted at 180 degrees phase shift (inverting filter configurations)

It doesn't mean the circuit on its own will oscillate. Look at the results of an RLC low pass filter: -



Clearly this circuit doesn't oscillate but, all the same, it has an oscillation frequency.