Is it right to talk about dynamic range on frequency domain? I'm comparing three frequency response's plots from simulations and experiments and I observed that two of them look like clamped to a DC component, where the max dB value is i.e. 100 and the min is 40 dB, while on the third one the max is i.e. 120 dB and the min is 10 dB. I want to use the correct term to talk about these intervals.

I've used the term dynamic range to express an amplitude variation interval on time domain, but is it right to use it on frequency domain too?
the dynamic range is the difference between the largest and the smalles value of a quantity can asume, so yes, you can have a dynamic range for the magnitud of your frequency components, I'm not aware if there's another terminology when dealing with the frequency domain. One thing to consider is not only the dynamic range of your signals but also the dynamic range of the variables you'rr using to store it and to calculate the frequency response, altough in the frequency domain (and specially when working with dB) it's not a big issue.