Generally speaking chromatic aberration has to do
with change in focusand/or magnification as function of wavelength.
Lateral CA is the change of magnification. That is, certain wavelengths
being magnified different from other wavelengths. This varies across
the lens - (i.e. edges).
All traditional optical systems suffer from this - some more, some
Purple fringing can be even seen in the center of images and seems
to be related to leaking between sensor cells.