I think what you're asking is how would one create a stop-band filter, or otherwise known as a notch filter.  There is no standalone notch filter in pd-vanilla that I know of, however, I usually use the [biquad~] object and look up the appropriate coefficients for the frequency I'm notching.  

  I believe this can also be done with [cpole~] and [czero~], which is shown in the pd-help H12.peaking.pd.  

Otherwise, there may be a stop-band floating around in a pd-extended library somewhere.