--in neurological circles generally means an onset of major symptoms, starting from a "no-symptom" state, that occurs in days to weeks. With neuropathy, generally anything that gets to a severe state in under three weeks is labelled "acute onset"; anything that gets that way in a month to three months or so is labelled "sub-acute onset".

If the symptoms take more than three months to "peak"--or definitely more than six months--the condition is likely to be labelled "chronic".

There is certainly some overlap, especially with the acute and sub-acute designations, but generally things come on very quickly, or very insidiously.