Added 9 October 2026 sspe noun Categories: Describing WordsRare Words noun ! Definition from WordNet 3.1, Princeton University. More about sspe at Wordnik → Where our words come from → A rare chronic progressive encephalitis caused by the measles virus and occurring primarily in children and young adults; death usually occurs within three years; characterized by primary measles infection before the age of two years. Related Words: bspdspedphasphcpisspsssppsspstpwspmeningoencephalitis Back to today's word